"Historians still argue as to whether Shakespeare was gay, a front for the Earl of Oxford and/or Sir Francis Bacon, or a cyborg from the future sent back in time to found Western civilization, thereby hastening the creation of the McRib sandwich."
The "revelation" that a famous historical figure actually had a secret life far more fantastic (figuratively or literally) and/or magical than history records. A historical retcon, if you will. Artists and writers tend to be the most common examples, followed by American Presidents. There is a subtly misanthropic theme if everyone remotely skilled at anything in history turns out to not be human or relying on special powers.
This is sometimes a way for a show to capitalize on sudden popular interest in some historical figure, or just to exercise a writer's pet interest.
In such a story, Plausible Deniability is almost always the order of the day; we have to be given this fantastic secret history in such a way that we can believe that the fantastic elements were kept out of public record.
In Time Travel stories, this often involves Retroactive Precognition, and one possible form it can take is You Will Be Beethoven.
Ancient Astronauts does this for entire ancient civilizations.
While the mixing of fantastic elements into historical texts is as old as mankind (see the Arthurian cycle for one example), the modern form of this trope probably originates with Dracula, essentially the incorporation of a fantastic secret life into the history of Vlad the Impaler.
See also Julius Beethoven Da Vinci and, for two particularly popular alien spies, Elvis Has Left the Planet and Rasputin The Mad Monk, and in anime, Oda Nobunaga. We Didn't Start The Führer is a subtrope of this. Often it leads to a Historical Badass Upgrade. May involve Gender Flipping, in which case expect a Samus Is a Girl reaction (or "Samus Is a Guy", if "Samus" was originally a girl in the first place) when the character's true identity is revealed. Contrast No Such Thing as Wizard Jesus. Also the Been There, Shaped History character where they simply use a fictional character. If the alien spy initially appears to be a fictional character, and only late in the story is revealed to be a historical figure, it's a Historical Person Punchline.
In Kamikaze Kaitou Jeanne, it is revealed that Jeanne d'Arc's military achievements were only a side thing — her real mission was to cleanse the worlds of demons.
In Master of Mosquiton, the mysterious Big Bad is revealed to be an immortal — most recently known as Grigori Rasputin — who had manipulated most of human history so he could fight against a monster that had exiled him on Earth, and was planning to eat the world's souls.
Given the polarizing effect he had on people, and how allegedly hard he was to kill, it shouldn't be surprising. The attempts to smear him before his assassination may only have served to make him more enigmatic, and thus more appealing to authors looking for such a figure.
Le Chevalier D Eon is built on this trope. At least two historical figures (including the titular character) share their bodies with the souls of their dead sisters and most others are involved in an arcane conspiracy and/or actual sorcerers themselves.
Code Geass: An alternate version of C.C.'s past in the Nightmare of Nunnally manga reveals that she is the "Witch Of Britannia". Since she was an Eden Vital, a witch, she didn't die. Her scar was cut into her by Joan Of Arc.
Read or Die - maybe. It contains "I-jin" which are clones of various historic characters, but with super-powers. It's a bit unclear exactly how powerful the original historical figures were supposed to have been - it's made clear that the I-jin have been "enhanced" during the cloning process. Most of the story revolves around a book written by Beethoven himself, suggesting that the original Beethoven was more special than generally known.
In Part 1, Jack the Ripper was turned into a zombie by Dio Brando.
It seems to be the case in Part 7, Steel Ball Run. The corpse parts they are traveling the USA to find are blatantly, almost outright confirmed to be from Jesus Christ. Making him one of the most powerful Stand users from the series, since he can actually pass Stand powers even after his death.
Haiyore! Nyarko-san has the various Lovecraftian abominations exist as alien species. H.P. Lovecraft wrote his stories based on what a Nyarlahotepian friend of his told him.
Steins;Gate takes internet hoaxter "John Titor" and makes his claims of being a time-traveling soldier entirely true. Her claims on her gender, on the other hand, are false.
In Dance in the Vampire BundAmbrose Bierce's mysterious disappearance is explained as him having been turned into a vampire, now allied with the Tepes clan. Grigori Rasputin was an alias of the vampire lord Ivanovic, who turned Princess Anastasia Romanova and kept her as a plaything. She later escaped and joined the Tepes clan.
The Big Finish Doctor Who audio The Kingmaker paints William Shakespeare in rather a different light, revealing that he was, later in life, actually Richard III. (He'd traveled back in time to goad the pragmatic and unpleasant-but-not-actually-villainous Richard into following the version of history outlined in his play, and ended up victim of a case of mistaken identity at Bosworth thanks to a broken arm and wounded leg. The Doctor sent the real Richard back to Stratford with some play outlines.)
Richard, for his part, had many experiences with aliens, having been visited regularly since his youth by time-tourists, who routinely pestered him about whether or not he was going to kill his nephews, and ran away if he mentioned doctors. And the Princes in the Tower? Well, they were actually girls, and following his relocation, Richard/Shakespeare raised them as his daughters.
The Eighth Doctor travels with Mary Shelley, and she bases Frankenstein on her experiences.
Howard Chaykin's Barnum!: In Secret Service to the U.S.A. has P.T. Barnum and his menagerie of sideshow entertainers thwart an assassination of President Grover Cleveland, then get recruited to stop Nikola Tesla's attempt to overthrow the United States.
Witchblade reveals Joan of Arc as one of the keepers of a mystical weapon (quite a few other historical warrior-women including Cleopatra and Mulan were wielders as well).
The Magdelena, from the same universe as Witchblade, is descended from a long line of women warriors sworn to protect the Catholic Church (and supposedly descended from the offspring of Jesus Christ and Mary Magdelene). She also wields the Spear of Destiny as a weapon.
This is partly because, with the exception of The Island of Dr. Moreau, Wells usually does not give his narrators names or complex personas. They more or less simply retell the action. Thus it is simple to use Wells in place of his characters.
Hilariously subverted in Fans!! when, after a time-travel-based encounter with robots and supernatural/alien life forms, Wells remarks that he wanted to write about things that weren't real and utterly fails to write his books. Even more hilariously, this leads to an Alternate Universe where he instead draws on the real life Kavorka Man aspect of his personality (helped along by one of the fans deciding it would be a good idea to sleep with him) and becomes a romance novelist instead.
The comic book series Lovecraft featured H.P. Lovecraft as its main character, revealing his stories were all based on actual adventures involving monstrous god-like extraterrestrial horrors he encountered and personally did battle with.
The aforementioned War of the Worlds: Global Dispatches makes nearly the same claim, but with a twist: Lovecraft's writing was inspired by his own suppressed memory that he is one of the godlike horrors the Martians had invaded Earth to escape.
The Atomic Robo story arc "The Shadow from Beyond Time" starts out with two issues where Lovecraft turns out to be possessed by a true Lovecraftian monster that breaks out and rampages through the streets of New York.
In the Image comic Invincible, the superhero known as "The Immortal" looks very familiar to students of U.S. history — one of his previous identities in his long life was Abraham Lincoln. Interestingly, this wasn't intended. Rather, it was Ascended Fanon on the part of the author when fans pointed out how much The Immortal looked like Honest Abe.
Matt Fraction's graphic novel The Five Fists of Science features Nikola Tesla teaming up with Mark Twain and Baronness Bertha von Suttner to bring peace to the world using a giant robot, and is opposed by a Lovecraftian cult lead by J.P. Morgan, with the assistance of Thomas Edison, Guglielmo Marconi, and Andrew Carnegie. The Morgan-financed cover-up of the comic's events is intended both to explain why Tesla, despite being a brilliant engineer, was later perceived as an unstable quack, and also to ground the story in true reality as a chapter of the main characters' lives that has been lost to history.
The Authority never comes out and says it, but via some well-placed art, hints that figures like Jesus, Gandhi, and Albert Einstein were previous Shamans. In addition, Einstein was apparently involved in at least one cross-dimensional adventure with Jenny Sparks.
In Howard Chaykin's The Shadow miniseries, Lamont Cranston is made into an ambassador of Shangri-La, like others before him. Including Clark Gable and Veronica Lake.
Helen Killer is the story of how Alexander Graham Bell gives an adult Helen Keller a device that allows her to see and hear, and she becomes a super-ninja, trying to stop the assassination of President McKinley and an attempt to turn all of the world's gold into lead to get revenge for losing out on the telephone patent. Seriously.
Luther: And just as I expected? Zombie Robot Gustave Eiffel! Ben: Alive! After all these years—!!
Issue 3 of IDW Publishing's comic book prequel to the 2007 Transformers movie establishes that scientists Robert Oppenheimer, William Hayward Pickering, Frederick Sanger and Jack Kilby were secretly working for the secret government organisation Sector Seven (as an Easter Egg, artist Don Figueroa added himself as another member). The movie includes other such information, but not as openly.
Also, according to the semi-senile Jetfire, his father was "The wheel! The first wheel!" And what did he turn into? "Nothing! But he did it with honor! Dignity, dammit!"
In the DC universe, Leonardo da Vinci was a member of the magic-wielding Homo Magi sub-species.
In the Marvel universe, Deep Throat was really a Skrull spy living as a government official, who had come to love the United States.
The Beatles aren't Skrulls, but they did have Skrull impersonators who went native.
And on the other side of the Kree-Skrull War, we had Dr. Walter Lawson, better known as Captain Marvel. Or Captain Mar-Vell, amongst the Kree.
Also in Marvel, immortal monster hunter Ulysses Bloodstone once went by "Captain Ahab" in the 19th century while on the hunt for a colossal whale-like monster; this fact bears the clear implication that he inspired Herman Melville to write Moby-Dick.
In 1602, Virginia Dare, the first colonist born in the United States, is a mutant with the uncontrollable ability to change into animals native to the New World.
One Spawn comic showed Houdini as a powerful sorcerer who uses his stage act to cover himself. He teaches the title character a few more tricks he can do with his hell-born powers. He even got a mini-series spin-offDaringEscapes and yes it is the same one as spawn makes a cameo and the bust spawn made is the macguffin.
Houdini also figured prominently in a DC Elseworlds special, "Batman: The Devil's Workshop", where a 1920s Batman teamed up with Houdini to fight vampires. Other Elseworlds books had historical appearances; "Dark Allegiences"(1930s) featured a plot to assassinate both Hitler and Roosevelt, and install a fascist leader in the White House, who would ally the US with the Axis during WWII, while "Detective 27" also featured FDR and Babe Ruth(talk about your Bat-Man!)
Related to that, Uri Geller is implied to have superpowers in Daredevil #133 (1976), and to have fought the villain Mind-Wave.
Hellboy extrapolates Hitler's real life fascination with the occult to astronomical proportions, up to and including an attempt to hire out the vampire Count Giurescu and funding a project to create artificial vampires to ravage Europe should the war's tide turn against him.
Rasputin wasn't merely a mad mystic—he was also friends with the Baba Yaga and a servant of the Cthuloid Ogdru Jahad. He hired himself out to Hitler in an attempt to use Nazi resources to cause the end of the world.
Earlier in Russian history than that, Peter the Great had three demons summoned to aid him in seizing Swedish land. As payment, they ensured that his sons would die young and that his heart would be cold and unfeeling.
Spanish webcomic-turned-comic-book El Joven Lovecraft ("Young Lovecraft") features young Howie summoning the monsters he'd later write about (a pet Ghoul, someone?), meeting Poe's ghost and overall having a boring pre-teenage life. The initial stip says that other works have fictionalized Lovecraft's history by either presenting him as a forced transvestite child or as an Indiana Jones-like adventurer fighting sectarian minions, but El Joven Lovecraft was to show, for the very first time, The Truth.
Vertigo's The Unwritten shows that several authors of world history have been secret agents of a conspiracy or were troubled by said conspiracy in giving life to the things they wrote (literally), e.g. Kipling.
In the French comic La Licorne, Ambroise Paré, Andreas Vesalius and other Renaissance scientists (including Paracelsus and Leonardo da Vinci) are members of a secret sect controlling the "Primordials", monstrous creatures that mimic legendary beasts such as griffins or dragons.
Spinnerette revealed that Benjamin Franklin travelled forwards in time to the desk of Adolf Hitler, where an assassin from the future promptly arrived to kill Hitler, but Franklin, not knowing the implications of the action, stops him and is accidentally pulled into a sort of time travel warp-tunnel. The assassin drops him in the year 2002 and continues on his merry way. Because he hadn't discovered electricity (required for time travel) yet, he's effectively immortal and invincible (e.g.: it is impossible to land a blow or shot on him) until he gets back, in order to prevent a time paradox. Presumably, no one realized what had happened until he showed up in 2002.
In The Secret History, this is the natural result of the Archons' conspiracies. A number of historical figures are aware of who and what the Archons are, and are able to assist them in their plots, sometimes using lesser forms of the runestones. Once tarot cards are developed as mini-runestones, they become known as "players." The players include Moses, Renaud de Chatillon, Nostradamus, Benvenuto Cellini, John Dee, William Sidney Smith, Napoleon Bonaparte, T.E. Lawrence, Rudolf von Sebottendorf, St. John Philby and his son Kim, just to name a few. Many real-life painters are employed to paint the tarot card sets, including Marc Chagall and Pablo Picasso.
In The Sandman, some of the historical figures have had encounters with Dream include Emperor Norton, Harun al-Rashid, and Shakespeare.
The Thunderbolts committed Jack the Ripper's murders in order to stop evil witch ghosts from claiming mortal hosts.
The Manhattan Projects has this as its central premise — almost everything you've heard about the scientists who shaped the latter half of the 20th century is a lie. Fermi? A man-eating, shapeshifting alien. Einstein? The real Einstein's less intelligent Evil Twin from an alternate universe. von Braun? Had a giant robotic left arm. And they're all working together to take over the world, and thereafter the entire galaxy. Mentions are made here and there of other noted figures in science, industry, and politics and what they're "really" up to in the same period; for instance, Soichiro Honda, founder of the car company that bears his name, designed samurai Mecha-Mooks for the Japanese military.
In the Italian comic book Gea, the eponymous character is a member of a group of super-powered individuals who work to send intruders from parallel worlds back, under the orders of a mysterious man known just as "the uncle" whom she's never met, bringing them to a nexus dimension. Said dimension looks a lot like the surreal landscapes of artist Roger Dean. Near the end of the series, Gea meets "uncle" and finds out he is Roger Dean - turns out his paintings were inspired by frequent visits in the nexus.
In DC comics history, more than a few of history's conquerors and despots were actually personae used by the millennia-old immortal villain Vandal Savage. Writers constantly flip-flop over whether Adolf Hitler actually existed in the DC universe, or if it was yet another of Savage's aliases. He's definitely Cain, though.
Chapter 36 of the Persona 4 fanfic Welcome to Tokyo implies that Alexander the Great, Julius Caesar, Oda Nobunaga, Joan D'Arc, and John F. Kennedy may have been Wild Cards, much like the main characters of the Persona games.
It is fairly common on Sentinel fanfiction to speculate that this or that historical figure may have been a Sentinel or a Guide.
Sonic X: Dark Chaos uses this as the core of its science-fiction universe. Jesus Christ, Satan, Muhammed, all the angels, and a large majority of the Jewish prophets from the Old Testament were all part of a vast universal conflict between the Demon Empire and Angel Federation. And Earth simply happened to be on a contested border between the two nations.
National Treasure depicts the founding fathers of America as the most recent safekeepers of a massive treasure trove.
Time After Time had H.G. Wells build a time machine and travel to the future in pursuit of Jack the Ripper, who happened to have been a friend of his. He meets a woman there and brings her back to his time and marries her.
His girlfriend makes a quip about becoming Susan B. Anthony although she probably wasn't being completely serious.
The girlfriend's name was Amy Robbins. Historically, Wells' second wife's name was Amy Katherine Robbins.
The second movie even had Michael Jackson begging Z to let him be an Agent, please Z, come on, he'd be the best Alien agent ever! He could be Agent M!
Unfortunate cameos ahoy... It also implies that Martha Stewart (or possibly her cat) is actually an evil(?) alien overlord.
The third movie reveals that Andy Warhol was actually "Agent W" and that his identity as an artist was merely to attract aliens to monitor. He was also completely faking his persona and actually had his death faked by K by his request.
A key plot point of The Prestige is the fact that Nikola Teslawas able to invent a device that created clones of whatever was put in it. He's also David Bowie, although that doesn't have anything to do with the plot (apart from being awesome).
This line is actually a reference to Chekov's running gag about things that were supposedly invented in Russia.
It's older than that, referring to a common joke about "Shakespeare in the original German." It's not that Shakespeare is a Klingon or a German, it's that the themes of his works resonate so powerfully with Germans/Klingons that they assume that he must have been one of theirs. It's a variant of Adaptation Displacement.
In Wishmaster 4: The Prophecy Fulfilled the Djinn implies he once served Caligula.
The film Bubba Ho Tep posits that Elvis Presley and John F. Kennedy (who has been turned into an African-American to disguise his identity) are secretly still alive in a Texas retirement home. Fighting mummies.
The Transformers movie showed that 5 US presidents knew about Megatron and The Cube. Hoover Dam was constructed to hide and store the Cube.
In the sequel, the Great Pyramids are a cover-up for an alien portal generator.
And in the third film, Neil Armstrong and Buzz Aldrin went to the moon to explore the ruins of a Cybertronian starship.
The Radix: Carl Gustav Jung was a leader of a cult that searched for the Radix, a miraculous plant that belonged to Jesus Christ.
In Daniel Handler's A Series of Unfortunate Events, the narrator and his comrades imply that V.F.D. dates back to Ancient Greece, that Martin Luther King, Edith Wharton, and Thomas Malthus were involved with it — although Malthus was on the evil side of the schism — and that Shakespeare may be alive. However, these may be the result of revisionism in accordance with V.F.D.'s own views.
This all led, eventually, to the title character being the 'mysterious wanderer' who interrupted the writing of "Kubla Khan".
According to Kage Baker's The Company Novels, William Randolph Hearst should have been a miscarried fetus before he was saved (very creatively) by a Company doctor. He later ends up an immortal and plays My Grandson Myself.
Greg Bear's Songs of Earth and Power does this with numerous personages to good effect.
Frank Beddor's The Looking-Glass Wars. Alice Liddell, according to the book series, is NOT who Lewis Carroll made us think she was. She was really Princess Alyss Heart, the daughter of the King and Queen of Wonderland who was exiled to the real world after her Aunt Redd staged a coup that killed her family.
In Children of the Lamp, it is stated that Harry Houdini was a djinn, possibly of the same tribe as the heroes.
In Sahara, Abraham Lincoln is captured by the South (a double is killed by Booth in the theatre) and is held captive on an ironclad, which runs the Union blockade and escapes to Africa, where it ends up trapped in the Sahara Desert after a river it followed dries up.
Atlantis Found reveals that Hitler and Eva Braun were actually cremated and interred in the same urn until Dirk flushes their ashes down the White House toilet.
Found, by Margaret Peterson Haddix, involved a future where rich families pay a corporation to go back in time and kidnap certain famous children (usually famous missing children, such as Anastasia and Charles Lindbergh Jr.), while they are babies. The children are then taken back to the future for these families to raise as their own. Except the ones that accidentally end up in our time.
A recurring joke throughout John Hodgman's Complete World Knowledge trilogy. There are too many of instances to fully list here. Just go out and buy the book.
The big one in The Areas of My Expertise is that President Hoover stole Tesla's inventions, built an army of robots, and tried to exterminate all the hoboes before they ascended to a higher plane of existence. Throughout the book are more "Were You Aware Of It?" lists, containing various "fun facts" about assorted historical figures. And Nick Nolte was one of the hoboes.
In Gabriel King's The Wild Road (and its sequel, The Golden Cat), The Alchemist (the series Big Bad) was actually Isaac Newton. Although this was never explicitly stated, enough hints were dropped to make it indisputably obvious.
In the kids' book Nosepickers from Outer Space by Gordon Korman, one of the titular aliens remarks that Shakespeare and Leonardo DiCaprio are aliens. When asked, he responds, "Could any Earthling write/act that well?" Other such aliens included Steven Spielberg, Michael Jordan, Mark McGwire and Stone Cold Steve Austin.
The Illuminatus!! trilogy did this with a large number of real and fictional characters; John Dillinger as a set of quintuplet Zen masters, Jesus as the world's first Bingo caller, Billy Graham as the Devil, and the Beatles as anarcho-capitalist prophets, among many others.
Perhaps most notably, Marilyn Monroe was trained to become an avatar of Eris (although her identity is only implied).
Jack accidentally kills Nemo, Jules Verne is running The Plan, Jamie Barrie is Peter Pan's greatest enemy after Captain Hook, also known as Mordred, Mordred and Merlin are brothers, their father was Odysseus, who was six generations removed from Deucalion son of Prometheus, their mother was Calypso, Arthur is the son of Merlin and married to a descendant of the Jesus (the Holy Grail), an alternate version of Charles burned down the Library at Alexandria, Mark Twain had an agent (Hank Morgan) at the tournament where Arthur became the High King and Hank's banner was a Cubs pennant, which apparently used to mean Triumph over Adversity, but now better represents Impossible Quests and Lost Causes, Jack is the Jack of Jack and the Beanstalk, the Pandora are a group of three witches, Mordred was the good guy until the fire of Alexandria and Merlin was the bad guy, "Aragorn" is a corruption of "Argo", Sir Arthur Conan Doyle and Harry Houdini were rogue Caretakers, Houdini had a pair of wardrobes that formed a passage between them and those were the inspiration for the wardrobe into Narnia, the Red Dragon ship was originally the Argo, the Yellow Dragon is the Nautilus, Pythagoras built Archimedes, a clockwork owl, Alexander the Great was descendant of the Argonauts, Verne was an apprentice of Twain, Caliburn (better known now as Excalibur) was the sword of Aeneas (a hero of the Trojan war and one of the possible ancestors of the guy who founded London), etc. These books are full of nothing but plot and this trope. Any genius in history was a Caretaker. Oh, and Da Vinci wasn't a genius, he was just a plagiarist. All of his sketches and paintings were originally by Bacon. Mona Lisa was smiling because Bacon was doing something rather obscene while he painted her.
Actually, not everyone was a Caretaker. It's revealed in Book 4 that several of the villains are the brilliant guys that were never given the proper chance to be Caretakers, and the fifth book in the series reveals that there's another society made of people that aren't Caretakers that includes Benjamin Franklin. Oh, and villains include John Dee and Nikola Tesla.
Tim Powers gives secret, supernatural histories to real-life figures in a lot of his works.
Last Call has Bugsy Siegel serving as the uncrowned emperor of Las Vegas while channeling the archetype of the Fisher King.
The Lightning Thief by Rick Riordan has a couple of throwaway lines to the effect that George Washington's mother was actually the Greek goddess Athena, and Harry Houdini was another demigod who successfully traveled to the Underworld and back.
One of the key plot points in the series is that the three chief gods (Zeus, Posiedon, and Hades) aren't supposed to father anymore demi-gods—in no small part because their recent offspring included every major player in World War II.
In Son of Neptune, Hazel notes that Hades/Pluto bears a very strong resemblance to Hitler.
Underground Railroad operator Harriet Tubman and Secretary of State William H. Seward were also revealed to have been demigods.
In the Percy Jackson universe, EVERY SINGLE famous person you have ever heard of is a demigod.
This leads to a bit of Fridge Logic when you remember that one trait of demigods is attracting trouble from mythical monsters. How did The Beatles go on tour without a minotaur ever causing an uproar at their concerts?
What do you think happened to Paul?
Some monster probably did, we just don't know it. Remember the mist?
Coach Gleeson mentions that General Sherman was a son of Ares.
Later in the Callahan's books, Nikola Tesla became a recurring character, having been made immortal by Lady Callahan and cured of his various phobias so that his scientific genius could aid Jake Stonebender and his friends in saving the world.
Scholastic's The 39 Clues claims that every single influential person in the world is a member of the Ancient Conspiracy family, the Cahills. And that they're all part of four hou - er, branches reminiscent of Harry Potter.
Well, not every single influential person in the world. Anyone born before the 16th century is out, for starters, and while the Cahills try to get people to marry into the family, it doesn't always work; Rembrandt is a canonical example.
Dan Simmons' The Terror adds a supernatural arctic menace to the doomed Franklin Expedition, which allows a lone survivor, Crozier. His Carrion Comfort blames many tragedies of the 20th century, such as Nazi atrocities and the assassination of John Lennon, on a lethal competition between sociopathic human mind-controllers.
Jamie Simons' children's book series Goners revolves around a group of time-traveling aliens trying to find out which historical figures were alien spies and bringing them home.
The Lensman novels reveal that many historical tyrants, including Nero and Hitler, were all guises adopted by a single alien spy - Gharlane of Eddore.
A variant occurs when the protagonists ask the Arisians if they interfered with human history in a similar fashion. While no great human leaders were actually Arisians, the character of Bergenholm (a fictional scientist from earlier in the book who developed a truly efficient FTL drive) was in fact one of their agents - for their Gambit Roulette to work, they needed humans to get proper FTL now. Bergenholm may not be real, but the impact on the characters was similar.
Thomas Wheeler's The Arcanum is about how Sir Arthur Conan Doyle, H.P. Lovecraft, Harry Houdini, and Marie Laveu are all members of a secret organization that protects the world from the occult.
In Laura Whitcomb's 'The Fetch', Rasputin is a cover identity being used by a supernatural being. Only Anastasia sees him as he truly is.
The Western Galactic Empire presumes (but does not prove) this of Shakespeare and, to a lesser extent, Jesus, in Robert Zubrin's The Holy Land.
The book and film Confessions Of A Dangerous Mind reveal gameshow host Chuck Barris's past as a hitman working for the CIA. This is probably fictional - though Barris insists otherwise.
According to The Autobiography of Santa Claus, King Arthur, Attila the Hun, and various other famous historical figures did not actually die, they decided to join in with old Saint Nick and the gang and gained immortality. Amelia Earhart even staged her own "mysterious disappearance" instead of finishing her flight around the world so that she could head up to the North Pole.
the Consul Cleopatra, not Shakespeare himself, but Christopher Marlowe, Raph the Renaissance artist Raphael, and Rasputin (which explains why he was so hard to kill).
This happened with Harry Houdini in what has to be the most awesome historical crossover ever, the short story "Under the Pyramids" by H.P. Lovecraft. Houdini goes on vacation, crosses paths with a sinister cult and winds up facing down the Eldritch Abominations of ancient Egypt. While he doesn't exactly emerge victorious, he does end up in far better shape than the typical Lovecraft hero. Now if somebody would just make a video game about Harry Houdini versus the Old Ones...
The Faction Paradox spin-off has had, at various times, Lord Byron, Percy Shelley, King George III, and Johann Sebastian Bach caught up in a Gambit Pileup involving the Time Lords and their quasi-Evil Counterparts. Oh, and Queen Charlotte is secretly a TARDIS — Shhh...
In Dacre Stoker's Dracula the Un-dead, Jack the Ripper is revealed to be... Countess Elizabeth Bathory.
In Tanya Huff's Blood Books series, vampire Henry Fitzroy was the Henry Fitzroy, illegitimate son of Henry VIII.
In The Door into Summer by Robert A. Heinlein, the protagonist (Davis) contacts a man who has invented a time machine. It is blatantly implied that the only person ever to have used the machine (an engineer who would have found himself marooned in a time too backward to make use of his advanced technical knowledge) was Leonardo da Vinci.
In the Night Watch books, the mythological Tibetan hero Gesar is head of the Moscow Night Watch. Joan of Arc was a weak dark witch. Thomas the Rhymer is head of the Edinburgh Night Watch, and was also an ancestor of Mikhail Lermontov.
In The Historian, the titular character is a vampirized Vlad the Impaler. Against the norm, Vlad explicitly isn't Dracula (as in reality, the novel is just loosely inspired by him), and instead of becoming a vampire the usual way, he became so through some medieval magic supposed to confer immortality note gone horribly wrong, as some monks found out when they performed it on one of their brethren, who naturally ate them. The title refers to Vlad's hobby since becoming a vampire. He created an immense library in his makeshift resting place with thousands upon thousands of books. Features to note are his first editions of Thomas Aquinias and one of the original Gutenburg printing presses.
In Elizabeth Bear's Promethean Age novels Christopher Marlowe, who may actually have been a secret agent, is taken into Faerie by Morgana after his "death". His place as a spy is taken by William Shakespeare and Ben Jonson. Eventually he sells himself to the devil and becomes a warlock. The three of them along with others contend with the Promethean Society, a secret society of sorcerers whose ranks include the Earls of Essex, Southampton and Oxford (The latter of whom is one of the popular candidates for the role of the man who "really" wrote Shakespeare's plays. In here he does cowrite some of Shakespeare's earlier works but his "help" is more of a hindrance.)
In the first Empire from the Ashes book, mutineers FROM SPAAAAAACE have been manipulating human civilization from the very beginning, and Hitler himself is singled out as being one of them. Evidently his enhanced body (strong enough to wield Gatling guns akimbo) is how he survived the attempted bomb assassination.
In the book Vampyres of Hollywood and its sequel, Love Bites, many Old Hollywood film stars and producers such as Mary Pickford, Theda Bara, Orson Welles, Charlie Chaplin, Douglas Fairbanks, etc. are actually vampires who used their abilities to mesmerize audiences on film. Many of them are actually responsible for popularizing false myths about vampires being vulnerable to garlic and holy symbols by depicting vampires that way in films so humans would underestimate them. Many of these old film stars faked their deaths and are trying to get back into the film business without being recognized as their old selves. Since the books were written by Adrienne Barbeau, they give a very detailed portrayal of Hollywood and the film industry from an insider's perspective, as well as a very detailed "what-if" scenario that shows Hollywood as being created and run by vampires from the beginning. There are a lot of humorous throwaway lines about various celebrities, such as a brief description of Joan Crawford as an out-of-control werewolf.
In the novel One Foot In The Grave the protagonist half-vampire encounters and enters into an uneasy team-up with the vampire that unintentionally transformed him into his partially converted state: Vlad Tepes aka Dracula. Vlad relates the atrocities he had to commit to protect his tiny kingdom from being conquered and his recent abandoning leadership of the vampire enclave in NYC (enclaves being scattered locations where vampires and other supernatural creatures attempt to live in secret and relative peace with human society and lead by a vampire lord with greater powers than the standard) in order to lead a more trouble-free life (didn't quite work out that way for him).
In Dracula Unbound by Brian Aldiss, Bram Stoker and a time-traveling scientist from the modern day fight vampires.
This was actually a sequel to Aldiss' earlier novel Frankenstein Unbound, in which the same time-traveling scientist encounters Doctor Frankenstein and his monster in the late 1800s, along with Lord Byron, Percy Shelly and Mary Shelly. He even ends up having an affair with Mary.
Tom Holland's novel Lord of the Dead reveals that Lord Byron was a vampire. Mad, bad and dangerous to know indeed.
Another famous vampire; in Christopher Golden's "Vampire Oddessy" trilogy, one of the main protagonist vampires is Buffalo Bill Cody.
In The List of Seven by Mark Frost, a young Arthur Conan Doyle gets swept up in a conspiracy against the British Government, working alongside a mysterious investigator named Jack Sparks. This adventure would inspire him to create Sherlock Holmes.
There is a series of novels by Michael Thomas that have Jane Austen as a vampire.
In The Stand, Randall Flagg claims to have been Cinque/Donald DeFreeze, one of the key figures in the Patty Hearst case and leader of the Symbionese Liberation Army.
Though the main character of The Madness Season was not historically significant, his father was an employee of the Library of Alexandria and his mother was worshipped in ancient times as a goddess (though we aren't told which goddess she may have been).
In James P. Hogan's "The Proteus Project" Winston Churchill, Edmund Teller and Albert Einstein, among others, work with time travelers to ensure a Nazi defeat (in the travelers' timeline they won.)
In Sacre Bleu Vincent van Gogh doesn't commit suicide; he's murdered by a millennia old shaman who works wiith the Muse of Painting. Other painters involved, past and present, with the duo are Toulouse Lautrec, Pissaro, Monet, Manet, Renoir, Michaelangelo, Seurat and Turner. The shaman, named The Colorman, is hinted to be the inspiration for Quasimodo. Later a drunken Lautrec gives his version of things to an equally drunken Oscar Wilde and it becomes the seed from which The Picture of Dorian Gray grows.
In the Legions of Fire Trilogy (commonly known as the "Centauri Trilogy"), part of Babylon 5's Expanded Universe, it is mentioned that there was a Drakh who once inhabited Earth—named Drak'hul.
The Hexer von Salem stories by German author Wolfgang Hohlbein, being grounded in his take on the Cthulhu Mythos, quite naturally have Howard P. Lovecraft himself as an important supporting character with actual if only occasionally used time travel powers who helps the main protagonist Robert Craven deal with the assorted horrors as best he can, especially early in the series. He's also a former high-ranking member of the actual (modern-day, which here means late 19th century) Knights Templar, who'd still like a word with him about quitting on them... — The series in general isn't at all shy about dragging famous historical or fictional characters into its plot, but Lovecraft is probably the most straightforward and prominent example of the trope.
Buddy Holly Is Alive and Well On Ganymede has the title musician as the pawn of the Illuminati. Or aliens. Or Atlanteans. Or all three.
In Amber Benson's The Ghosts of Albion series, the mystical Protectors of Albion are aided by the ghosts of Lord Byron, Admiral Horatio Nelson and Queen Boudicea, the last of whom was killed by a demon.
In Kim Newman's Bad Dreams Joe McCarthy, Roy Cohn and Ayn Rand are all pawns of a vampire.
Orson Scott Card's The Tales of Alvin Maker series has a subtle variant, since it takes place in an Alternate History version of 19th century America where folk magic and supernatural "knacks" are accepted parts of everyday life. Among other tidbits, Napoleon Bonaparte's military career is made possible because he has a knack that makes people trust and obey him, William Blake becomes a great poet because he has a knack for prophetic visions, and Tenskwatawa becomes a revered Shawnee leader because he's a genuinely powerful prophet and Earth wizard.
In Laura Anne Gilman's Cosa Nostradamus universe the founder of the system of modern magic and, to a large extent, of modern magical society is Benjamin Franklin.
In one Angel episode, during a chase through an art gallery, to shake pursuit he briefly pauses to lecture on a painting of the French poet Baudelaire, suggesting that Baudelaire's poem "The Vampire" was based on an encounter with a real vampire (possibly Angel himself, as he tells his audience that Baudelaire was actually "a little taller and a lot drunker" than he appears in the painting).
Angel also tells Roger Burkle that Spiro T. Agnew was a demon during "Fredless".
In "I've Got You Under My Skin", Wesley tells us that Lizzie Borden was possessed by an Ethros demon.
In "The House Always Wins", Angel tells Fred and Gunn that two members of the Blue Man Group are demons.
In "Why We Fight", one of the vampires captured by a WWII-era US submarine claims to have been Rasputin's lover.
One rather forgettable Smallville episode had an immortal being trying to collect Kryptonite-infected organs to grant his true love immortality. (It sort of makes sense in context). Chloe says "I didn't come here to get carved up by some Jack the Ripper wannabe!" He smiles and says, "I was Jack the Ripper..."
In the Babylon 5 episode "Comes the Inquisitor", the Vorlons send a human named Sebastian to act as their Inquisitor. He acts, sounds, and dresses like a late 19th century upper-class Englishman, and claims he was taken by the Vorlons to do their bidding and is kept in suspended animation when he is not needed. He explains at the end that he thought he was chosen for a special destiny, but was wrong. And history was not kind:
Sebastian: Good luck to you in your holy cause, Captain Sheridan. May your choices have better results than mine — remembered not as a messenger. Remembered not as a reformer, not as a prophet, not as a hero, not even as Sebastian. Remembered only... as Jack.
A more literal case is that of Jeffrey Sinclair, shifted backward a thousand years in time and physically transformed into the Minbari religious figure (and hero of the previous war against the Shadows) Valen.
In the Bewitched episode "Twitch or Treat", baseball star Willie Mays is shown to be a warlock.
Blackadder begins with the claim that the historical reports of Richard III are a near-total fabrication. Indeed, the first series presupposes that there was a decade-long interregnum between the death of Richard III and the accession of Henry VII Tudor, one that saw the reign of Richard IV, (who in actual history, was one of the child "Princes in the Tower," presumably but never proven to have been murdered on the orders of Richard III) before a bungled murder plot by Baldrick and Lord Percy of Northumbria against a group of ne'er-do-wells bend on killing the Royal Family kills the entire Plantagenet line, leaving the way open for Henry to come in and rewrite history as if he had won at Bosworth Field in 1485.
The series would make similar claims about other historical persons, such as Oscar Wilde, who, according to Blackadder, was the father of hundreds of illegitimate children and the author of a pamphlet entitled "Why I Like Doing It With Girls." Any evidence to the contrary is the work of a very skilled prosecuting attorney with a grudge.
They also claimed that all the famous female writers during the Regency era were men and that Jane Austen was really a huge Yorkshireman with a beard like a rhododendron bush.
In the episode "Selfless", we find out (via flashback) that Anya had a hand in causing the 1905 Russian Revolution.
In a Season 6 episode, Anya claims that Martha Stewart is a witch, and that this is how Stewart has accomplished certain things she is famous for.
Buffy realises mid-history class that Rasputin might have been a vampire, explaining the difficulty they had in killing him.
And after another class expresses doubts that Charlotte Corday really killed Jean-Paul Marat—his death looked more fangy than knifey to her.
In the Musical Episode Sweet sings that he gave Nero his very first fiddle, implying that he's responsible for the Great Fire of Rome and the Temporal Paradox caused by introducing a musical instrument centuries before it was invented.
In the Origin graphic novel, Merrick tells Buffy that Emperor Caligula and Jack the Ripper were both vampires - or, more accurately, the same vampire.
Tales of the Vampires shows that, indeed, Jack the Ripper was a vampire. Tales of the Slayers also implies that Joan of Arc was a Slayer.
Tales of the Slayer also tells us that General William Tecumseh Sherman was a Watcher (sort of.)
Three counts Admiral Nelson amongst his personal friends.
The Fourth Doctor's scarf was made by Madame Nostradamus ("a witty little knitter").
Also, Janis Joplin gave the Doctor his tenth incarnation's coat.
The Doctor has admitted to sitting in a tree and dropping apples on Newton's head.
In "The King's Demons", the Fifth Doctor thwarted the Master's attempt to replace King John(whom the Doctor declared was a fairly decent king, as far as The Dark Ages went) with an android in order to prevent the signing of the Magna Carta.
"Timelash" reveals H. G. Wells to have been inspired by a short trip with Six.
"Silver Nemesis" revealed that the Doctor had launched the Nemesis weapon from the Earth inside a satellite to keep it out of the hands of his enemies, only to have that satellite's orbit bring it close to the Earth every 25 years, where the weapon's energy would adversely affect Earth history. The Doctor claimed that Nemesis may have influenced the start of World War II and the asassination of President Kennedy.
"Tooth and Claw" reveals that Queen Victoria faced a werewolf (implied to be the source of the haemophilia widespread among European royalty in the late 19th century), and subsequently set up the Torchwood Institute.
"The Girl in the Fireplace" followed the life of Mme. du Pompadour as she faced clockwork robots.
"The Shakespeare Code" had Will involved with real witches.
"The Unicorn and The Wasp" had a murder mystery surrounding Agatha Christie... involving a Giant Shapeshifting Space Wasp. (The trope is also Lampshaded in this episode: "That's like meeting Dickens at Christmas... with ghosts!" — this was also a Shout-Out to the above mentioned episode "The Unquiet Dead".) The events of this episode led to Christie's 11-day disappearance in December of 1926.
"Victory of the Daleks" sees Eleven helping old friend Winston Churchill with the Daleks.
In "The Vampires of Venice" Eleven is momentarily worried about running into Casanova, to whom he owes a chicken, until he realizes he is 140 years too early. Even funnier when you realise the previous Doctor's actor has also played Casanova.
In "Vincent and the Doctor", Eleven and Amy team up with Vincent van Gogh to track down a monster. The Doctor also namedrops Michaelangelo and Picasso.
Eleven may have been directly responsible for the Watergate scandal, as he advised Richard Nixon to 'tape everything' in an effort to defeat the Silence in "The Impossible Astronaut" and "Day of the Moon".
Nixon: "Dare I ask - will I be remembered?"
The Doctor: "Oh, Dicky. Tricky Dicky. They're never going to forget you! Say hello to David Frost for me."
"Dinosaurs On A Spaceship": The Doctor helped Ancient Egypt's Queen Nefertiti out with an attack by weapon-bearing giant alien locusts, and she in turn helped with the dinosaurs of the title.
"The Power of Three" sees Amy accidentally get married to Henry VIII, and the Doctor comment that Fred Perry(a famous tennis player from the 1930s) would probably want his shorts back.
A future incarnation of the Doctor ends up as the Merlin of an alternate universe in "Battlefield".
It has been hinted that the Doctor was rather friendly with Elizabeth I, the so-called "Virgin Queen". It's confirmed when the Tenth Doctor uncovers a Zygon plan to replace her in "The Day of the Doctor".
Steven encounters several of the people involved in the 16th century St. Bartholomew's Day Massacre.
Happened in real life in the case of the Third Doctor's actor Jon Pertwee; he was an awesome Doctor, but it eventually came out that he was also a British spy for the government during his time in the Navy (Hence his love of cool cars, gadgets, and fisticuffs).
In Torchwood, Jack apparently had flings with Oscar Wilde and Christopher Isherwood.
In American Horror Story: Coven, singer Stevie Nicks is a powerful witch nicknamed "the White Witch" who is a long-time member of the coven and actually appears in one episode to help convince Misty to join the coven.
Also, Myrtle is certain Leonardo da Vinci was a warlock, though it's never been proven.
Tales From the Crypt spin-off Perversions of Science, in one episode, similarly has Orson Welles trying to flush out two real Martian spies by making them think the invasion has begun without them. All to get them out of the way for him and his Jupitarian brethren to begin their own invasion!
Similarly, the Big Finish Doctor Who audio play "Invaders from Mars", while not claiming the radio play was inspired by real events, works it into the story by having the Doctor use it to persuade some not-especially-bright aliens that Earth has already been invaded, by a force far superior to their own, making it a poor choice of breeding ground.
First Wave is predicated on the assumption that Nostradamus was actually doling out coded information about an alien invasion and was, in fact, an alien himself.
Grimm has hinted, or sometimes outright said, that various historical figures/celebrities were/are Wesen, and Nick's family history has shown Grimms as 'also present' at various historical events (e.g., on board the "Beagle" with Darwin.) Notably, Adolf Hitler was a Blutbad (some sources also claim that he was a Schakal, but Wordof God confirms the Blutbad version), using the Coins of Zakynthos to get people to follow him.
One of the tie-in novels had Niccolo Machiavelli as an Immortal.
In the Wayne and Shuster spoof "The Tail-light Zone", Johnny Wayne plays a man who has secretly been prolonging his youth for centuries. When told he knows more about the past than the scientist who found the Dead Sea Scrolls, he bursts out laughing. When asked why, he says, "I'm the one who lost them!"
The Masters Of Horror episode "The Washingtonians" (and the Bentley Little short story from which it was adapted) spins a tale of how George Washington was secretly a prolific cannibal, and the only people who knew this were part of a cult of cannibals in Revolutionary War-era clothes and wigs. Also, Benjamin Franklin apparently never existed and is based on the accomplishments of several lesser individuals.
Dark Skies is almost built around this trope, including such notable individuals as JFK and Norman Schwarzkopf as part of the story.
Sanctuary tells us in its first episode that Jack The Ripper is an ageless metahuman with the power of teleportation, who was a pretty nice guy until the cumulative brain damage caused by the use of his powers drove him murderously insane. Oh, and he's father of one of the series regulars, having once been engaged to Dr. Magnus. A handful of episodes later, we discover that Nikola Tesla is an immortal, electricity-shooting vampire. But he really did legitimately think that that his death ray would result in world peace. He even had his Nobel speech prepared. All of them gained immortality of one sort or another by injecting themselves with vampire blood.
Furthermore, James Watson, who in real life discovered DNA, is in Sanctuary a few decades older, a member of the same group of metahumans as Jack the Ripper and Nikola Tesla, and was the real-life inspiration for Sherlock Holmes (having insisted on having his name shifted to the sidekick).
And if Helen Magnus is to be believed, more famous people than not were secretly "abnormals". For example, William Howard Taft had such a brief presidency because he had difficulty staying in human form, and asks what normal human would want the job in the first place, implying that this applies to multiple presidents.
Oh, and also, vampires used to rule the world, and an innumerable number of ancient rulers were vampires until humanity rose up against them.
The Real Life master criminal Adam Worth was actually a brilliant scientist on par with the Five (but much more ruthless) who snapped after his daughter died of leukemia, developed a second personality, and went on a Roaring Rampage of Revenge.
An episode of short-lived HBO sci-fi anthology series Perversions of Science concerns a murderous Mad Scientist from the future who, upon being found incapable of rehabilitation, is sentenced to be exiled to mid-20th century Germany, but not before his jailer, on a random whim, shaves the prisoner's facial hair down to a toothbrush moustache.
In Saul Of The Mole Men, Benjamin Franklin was the keeper of two of three legendarily powerful stones, or, as he called them, "igneodes". This was in addition to being the first man to encounter the Mole Men, which also sparked his invention of "interspecies erotica." Oh, and Thomas Jefferson was a brutal Ax-Crazy murderer who skinned Franklin alive for the power of the "igneodes".
There's also John Henry, the steel driving man of legend, who defeated the steam engine but survived, and eventually drove his way into the depths of the earth and became a cyborg; one with the engine he had once called his enemy.
Also, in "Wolf in the Fold", Jack the Ripper is revealed to have been an alien.
Star Trek: Deep Space Nine: In "The Muse", there's a non-corporeal alien seductress who psionically inspires humanoids and feeds off the neural energy produced by their creativity, a process generally fatal to the inspiree. She claims to have inspired the Earth poets Catullus and John Keats, as well as some future artists.
In "Little Green Men", we find out that an alien ship actually did crash at Roswell in 1947. It was Quark's shuttle.
Star Trek: Voyager: "The 37s" reveals that Amelia Earhart was among the victims of a massive Alien Abduction plot. This is perhaps the most well-researched part of the story.
Supernatural: Samuel Colt made a gun that could kill anything.
Which also unlocks the gates of Hell. Which are located in the middle of a giant devil's trap made of churches linked by private railroads. Which Colt owned.
The episode "Crossroad Blues" strongly implies that Robert Johnson, Mozart, Van Gogh and other famous people that displayed great talent and died young had sold their soul to the Devil.
The season 6 finale states that H.P. Lovecraft's writings were inspired by regular glimpses he got of the things lurking in Purgatory, and that he was eventually killed by one of those things.
And the seventh season episode "Time After Time" reveals that Elliot Ness was a hunter.
As revealed in Season 9, L. Frank Baum was a Man of Letters, who based the Oz books on the adventures his daughter Dorothy (herself a hunter) had in Oz.
One The Tomorrow People serial revealed that Adolph Hitler was, in fact, an alien warlord. And had been secretly frozen at the end of the war. And used hypnotic mind-control powers to make people think his ideas about racial purity were a good idea. Seriously.
...But Albert Einstein was a Jewish pantheist (he saw God as a metaphor for the wonders of the universe), and Mark Twain an atheist.
And the Christian God/his angels cannot help those who do not believe in Him?
If memory serves one of their main lines was 'accept that God loves you' so...
Warehouse 13: Thomas Edison invented vehicles that run off the users' body heat. Philo Farnsworth invented a two-way video-audio communicator. Nikola Tesla, Thomas Edison's "nemesis", created an electric stun gun/Neuralyzer. Lucrezia Borgia owned a Mind Control comb.
In fact, the series is all about magical objects that belonged to famous people, so it is going to thrive on this trope.
A few artifacts invert this trope, they seem to have mystical powers due to the fame of their owners.
The second season reveals that H.G. Wells is an evil genius, formerly held in suspended animation in the Warehouse...and a woman.
Paracelsus appears as the villain of the 4th season finale/5th season premiere, he was caretaker of Warehouse 9, and he tested a philosopher's stone on his brother (the Count of St-Germain) but was bronzed for attempting to wrest total control from the regents.
"The Unnatural" is about a gifted Negro baseball player in 1947 who turns out to be an alien Grey. The person telling Agent Mulder this story suggests that all the great baseball players were aliens, which is too crazy an idea even for Mulder.
The player is strongly suggested to be Josh Gibson, one of the greatest Negro Leagues players of all time. Not only was Gibson a prolific home run hitter with the same first name as the player in this episode, he also spent most of his career playing for the Homestead Grays (the team in the episode was the Roswell Grays). Furthermore, early in the episode, Mulder was running through the names of some baseball Hall of Famers, asking his informant whether they were aliens. When Mulder asks, "Gibson?" the informant responds with "Bob or Kirk?", omitting the (arguably) much more accomplished Josh.
A Harry Turtledove short story reverses this, with an ordinary human baseball player who's a knuckleball thrower. A visiting alien is convinced by his throwing that he has telekinesis.
George in My Hero mentions that Einstein and Mozart were human-Ultron hybrids. Leonardo da Vinci is a full Ultronian. As Arnie puts it: "He was designing helicopters and tanks in the 15th century. Does that sound like normal human behaviour?"
Just like its comic book counter part, Witchblade mentions several people as wielders, including Eve (as in Adam and Eve), Joan of Arc, Irish queen Boudicca, the lover of Irish king Conchobar, Florence Nightingale, even the mother of the real girl behind the story of Little Red Riding Hood. Nottingham is shown to be a reincarnation, as well. Longinus is also shown as a murderer still living in the modern day, who can only be killed by the blade.
In Stargate SG-1, the Chinese emperor Yu the Great was really a Goa'uld System Lord. Also one of the good ones (not nice enough to fully turn against the Goa'uld and become a Tok'ra, but he was good to his people instead of being a tyrant, and has no beef against Earth.)
Primeval reveals that Spring-Heeled Jack was actually a velociraptor.
In Gilligan's Island there is a "James Bond" dream-sequence spoof episode that does this almost literally. Gilligan (as Agent 014) explains to his boss (the Professor) that the greatest secret agent ever was...Beethoven. Professor: "I didn't know Beethoven was a secret agent!" Gilligan: "See how good he was?"
The pilot of NBC's Dracula casually reveals that Jack the Ripper was a myth created by the Order of the Dragon to hide a vampiric killing spree (they mutilated the victims to hide that they'd been fed on, and wrote the letters).
In Sleepy Hollow several Founding Fathers, especially Washington, Franklin and Jefferson, are involved in the plan to stave off the apocalypse. Washington also is briefly resurrected as "Zombie Washington" as part of the plan.
The They Might Be Giants song "Ballad of Davy Crockett in Outer Space," performed to the tune of the original Davy Crockett song. "Messin' around with the fabric of time / He knows who's guilty before there's even a crime. / Davy Davy Crockett, the buckskin astronaut / Davy Davy Crockett, there's more than we were taught."
Nephilim. This whole French role-playing game's background was solely designed to allow game-masters to re-write History and incorporate it in their scenarios in any way they liked. They give you a basic backstory about the world; then you are supposed to study your region's various historical details to build up various conspiracy theories. Even if that's not your thing, the way they rewrote the entire history is absolutely overwhelming; evil secret societies trying to take over the world galore! Then they explain very seriously to you that the myth of modern Santa Claus was solely created to put back the actual Saint Claus in the collective imagination, in order to liberate him from the parallel dimension he had been put a millennium before. And don't get me started on Joan of Arc, Atlantis or the Dinosaurs... This game just defines the trope and has exploited it further than everything else.
Diana almost became a member of the X-Men splinter group X-Statix, as depicted here◊.
The Old World of Darkness used this all the time. Most every sourcebook includes at least one, and typically more than one, historical figure, though not always a highly well-known one.
Averted with one historical group: Nazis. After a few missteps (including Himmler as a vampire in Berlin by Night) in First Edition, the creators came to believe that painting World War II as the product of supernatural influence would remove some of the basic horror from it and "cheapen" the events of the war, as well as be somewhat awkward since there are still people alive who were affected by the war. As a result, all horrific events within the past 100 years had been deemed off limits to writers. This rule was swiftly invoked following 9/11, when all sorts of crazy supernatural whodunnits started to pop up in "explanation."
The basic rulebook in Vampire: The Masquerade features a historical account of Vampire society through the ages, with annotations from a powerful Sabbat member. When World War II is addressed, in an interesting use of the "avoid awkwardness" rule, said Sabbat member muses upon the fact that the Camarilla always tends to underestimate the capacity of humans to perpetrate great evils upon themselves, and that with the Kindred's loss of humanity a certain flavor of evil seems to have been lost as well.
Wraith The Oblivion plays with this; being about ghosts, it can have various historical figures continue on in the Underworld without rewriting their established histories. That said, historical importance is no guarantee of post-mortem importance.
Hunter The Reckoning is an aversion, with the imbued first showing up around 1999 (the year of the game's release), and none of them being well-known. There're theories about historical antecedents, but nothing solid.
One interesting twist: Rasputin. Several sourcebooks claim him as a supernatural, but each time a different sort of supernatural, suggesting...what? Canon Discontinuity? That the World of Darkness is built on multiple non-exclusive truths? Lampshading the authors' own practices? That Rasputin is a Ninja Pirate Zombie Robot? The Malkavian source book has the insane clan claiming him as one of its members, and his slumbering place in Asia Minor being responsible for the turmoil in Russia and the Middle-East. Probably lampshades the tendency of all clans to claim a greater influence on human history than they actually have. The 'official' answer: the 'real' Rasputin became a wraith after his death, and gleefully possesses various supernaturals.
Genius The Transgression, being a fan-made game, can get away with it. Only three of the world's great inventors were Geniuses: Leonardo da Vinci, Nikola Tesla, and Enrico Fermi. Of them, the latter two were part of the Genius status quo while Leonardo rebelled against it. Notable in being justified however, as Tesla in particular fits the mad science nature of Geniuses to a tee.
The Halifax Explosion was caused by a battle between Pentacle Mages and a Church Militant branch of the Seers of the Throne, and Task Force VALKYRIE first came into existence when they hired the actor who'd stand in for Lincoln during the infamous night at the theater... to cover up for the fact that some thing had already eaten the president.
Vlad Dracul became a vampire, founding his own covenant, the Ordo Dracul.
The "person from Porlock" who stopped Coleridge from finishing Kubla Khan was actually a Promethean who sensed Coleridge was inspired by a qashmallim and felt it necessary to disrupt its plans. A Promethean also caused The Tunguska Event by trying to summon one of said qashmallim, despite the Knights of St. George's best efforts to stop him.
The d20 Modern supplement Menace Manual lists a number of organizations, both fictional and real, for use in games. One of the organizations is the Final Church (orginally from Dark•Matter), a satanic cult. The entry states that Hitler and the other high-ranking Nazis were members, and the Holocaust was actually a human sacrifice of vast proportions.
And the small-press RPG Shattered Dreams claimed that Hitler wasn't initially evil, but was driven mad by Vacyge who'd invaded his nightmares.
A somewhat meta example: In the "Masque Of The Red Death" spin-off from the Dungeons & DragonsRavenloft campaign setting, we get an alternate Earth stalked by the usual cast of supernatural villains, Dracula etc. etc. Also the fictional James Moriarty is real, and for some reason a rakshasa.
The GURPS Who's Who sourcebooks cover realistic stats, personality, and recommended campaign usage of 104 historical figures. Also included is a "What if?" section for every person, suggesting possible deviations from accepted history. Some of the more fantastic suggestions that other works on this page haven't covered include Mozart being assassinated for encoding Illuminati secrets in his music and Mata Hari being a time traveling grad student studying Europe before and during WW1 with a Snowball Lie alias.
The Shadowrun game-setting was rife with this for a while, back when the writers were stuffing it with historical ties to Earthdawn. Figures such as Elizabeth I and (yet again) Leonardo da Vinci were revealed to have been immortal elves, left over from the Fourth World and killing time while awaiting the next Awakening of magic.
In Unknown Armies, any number of celebrities past and present are listed as Avatars (people who channel archetypes to gain god-like powers). This list includes Joe McCarthy as The Demagogue, Amelia Earhart as The Flying Woman, and Neil Armstrong as The Pilgrim, amongst others.
In addition, a school of magic called Iconomancy allows its practioners to channel the famous dead. Curiously, you can't channel Jim Morrison. One wonders why...
Because the only person that can channel Jim Morrison is Morrison himself, who is currently living in Los Angeles.
Deadlands has some of these, including Abraham Lincoln (Harrowed following his assassination), Jefferson Davis (killed and replaced by a shapeshifter), and Edmond Hoyle (whose Book of Games is the coded grimoire of the hucksters).
Rifts: England revealed that Merlin is an evil immortal being that had been trying to take over the world when he was helping out King Arthur.
There's a Savage Worlds setting entitled "The Day After Ragnarok," in which much of the Western Hemisphere has been destroyed in the aftermath of the Nazis' plan to summon Jormungand, which was successful until an American plane flew through the World Serpent's pupil and detonated a nuclear bomb in his skull.
In Witch Girls Adventures Gilgamesh was not only genuinely the superhuman The Epic of Gilgamesh paints him as, but was the only son of the first witch, Lilith (Not the Lilith, but almost certainly the inspiration for her in the game world); progenitor of a race of immortal superhumans which included King Arthur; and the father of Zephyr. Compared to that, the other examples are downright mundane — Vlad Dracula is actually an evil vampire and was a major player in the now-secret supernatural portion of World War II, and Lovecraft (not referred to by name, but described in terms that leave little doubt) was an acolyte of a race of Eldritch Abominations — the book only briefly covers his involvement and doesn't make it clear whether he outright worshipped them, or just formed a belief system that integrated his knowledge of them.
Nobilis 2nd ed. offers Isaac Newton as the Power of Motion and Johann Sebastian Bach as the former Power of the Fugue.
3e's "A Diary of Deceivers" mentions Ronald Reagan and several of his staffers were killed and resurrected by an Excrucian Deceiver.
Warhammer 40,000's major background character, the Emperor, is an immortal, incredibly powerful psyker who adopted various guises as he subtly guided mankind's evolution - it's known that he was Saint George, and implied that he was even Jesus. It was only when subtlety failed that he stepped out of the shadows and emerged as the founder of the Imperium.
John Adams: [Ben] Franklin smote the ground and out sprang George Washington, fully grown and on his horse. Franklin then electrified him with his miraculous lightning rod and the three of them — Franklin, Washington, and the horse — conducted the whole revolution by themselves. Ben Franklin: ...I like it.
This is almost written word for word in one of Adams' letters. Adams is talking about what later people will tell. I think it's safe to say Ben Franklin could not actually conjure generals on their horses.
Michael Jackson ONE presents the late musician as an embodiment of magic and wonder to the point that its misfit protagonists gain magical abilities when they find and use his iconic wardrobe pieces. An enforced example because this Cirque du Soleil show is co-produced by Jackson's estate.
The series Shadow Hearts is full of varying degrees of this, from H.P. Lovecraft being able to summon monsters, to Mata Hari being pulled into a quest to save the world from evil sorcerers.
Castlevania: Bloodlines plays with the story of the original Dracula novel, stating that Quincy Morris had a son, John Morris, and that the family was related to the Belmonts.
Eternal Sonata's main character is Frederic Francois Chopin. Yes, the famous pianist and composer.
The whole game's set in the fever-induced deathbed dreams of Chopin himself...
Though it's probably lost on anyone not familiar to Japanese history, Ōkami suggests and eventually confirms that historical figure Minamoto no Yoshitsune is a 200+ year old Moon-born celestial. For those wondering when Yoshitsune was ever shown or even mentioned in the game, just remember that his childhood nickname was Ushiwaka
Near the end of the game Destroy All Humans! 2, it is revealed that Lenin, Stalin, and Khrushchev were either influenced by the Blisk, crablike aliens from Mars, or were themselves Blisk in disguise. It's also implied that the Blisk also mated with humans thousands of years ago, and that perhaps the Russians are the decendents of those matings.
The plot of the 2nd Gabriel Knight. Mad King Ludwig of Bavaria was seduced by a charismatic male werewolf (Which actually indicates nothing about Ludwig's sexual preference; Even the Guys Want Him, and the same werewolf, it is all-but-explicitly-stated, seduces the otherwise straight Gabe), and that Ludwig and Richard Wagner had worked together to create an opera which, when performed under the acoustic conditions specially engineered into Neuschwanstein Castle, would trigger a werewolf's transformation involuntarily. Ludwig's purported "madness" was a cover for lycanthropy.
Assassin's Creed gets a ton of mileage out of showing how nearly every historical figure was secretly a Templar, a group dedicated to controlling humanity from behind the scenes, or an Assassin, the opposing group who believes humans should be free to live however they want, or were somehow affiliated with the two groups. Most evil people were secretly Templars and most good people were secretly Assassins, but sometimes the games like to throw in a surprise.
Assassin's Creed: Takes place during the Crusades when the Templars were working openly, so naturally Robert de Sable was a Templar.
In Assassin's Creed III, most of the Founding Fathers were neither Templar nor Assassin, except for Charles Lee, who was a Templar.
In Assassin's Creed IV: Black Flag, Charles Vane and Benjamin Hornigold were Templars, Mary Read was an Assassin, and Black Bart was an immortal who is born into a new body with all of his old memories and physical appearence every time he dies.
Throughout the series and supplemental material, even objects have been given this. Notice how many famous orbs, staffs, pieces of cloth, and swords there are in history?
Imperishable Night features Reisen Udongein Inaba, a Moon Rabbit who fled to Earth during the Lunar War between Earth and the Moon, in which Neil Armstrong was heavily involved; and Reisen's mentor on Earth, Eirin Yagokoro, was responsible for what happened to Apollo 13.
Ten Desires features Toyosatomimi no Miko, a.k.a. Prince Shoutoku, except that spreading Buddhism across Japan was only used to control the people, while "he" secretly pursued immortality through Taoism. Oh, and "he" was actually a girl.
The Neverwinter Nights module "The Bastard of Kosigan" has an ancient civilization of primordial hyper-advanced humans playing god (or more specifically angels (the 'control' faction, led by Gabriel) and demons (the 'free will' faction, led by Elisa Than (geddit? Elisa Than? Satan?))) to use humans as proxies in their constant war with each other. Among other things, Jesus was sponsored by the demons (the apostles John (who you get to meet) and Judas were immortals, the rest were normal humans and actually believed it all), Gabriel did appear to Muhammad in a dream, the demons set off the barbarian invasions to destroy the corrupt Roman Empire the angels had set up, and the angels created Catholicism to use Jesus' message against those who sent him in the first place.
In Team Fortress 2, it is revealed that there have been several generations of predecessors to the mercenaries we all know and love, and that the first generation was an... interesting bunch. For instance, the original ensemble included Billy the Kid (Scout), Stonewall Jackson (Soldier), Abraham Lincoln (Pyro), Nikola Tesla (Engineer), John Henry (Heavy), Alfred Nobel (Demoman), Sigmund Freud (Medic), Fu Manchu (Spy) and Davy Crockett (Sniper).
Abraham Lincoln also invented stairs, before he was assassinated by John "Tower of Hats" Booth.
The rocket launcher, the two-story house, America and the stage play were all invented by Shakespearicles, the strongest writer who ever lived.'
George Washington's greatest regret was not being permanently invisible. The Cloak and Dagger lets the Spy do just that.
Similar to the Kamikaze Kaitou Jeanne example above, the PSP game Jeanne d'Arc has Jeanne as a magical girl fighting an invasion of demons spearheaded by a demonically possessed King Henry and the Duke of Bedford, who used to be a demon-battling hero himself. Although this may not qualify, as it doesn't seem to take place in our 15th Century Europe.
Interstate '76 avoids this trope, but the sequel Interstate '82 plays it straight. The game's Big Bad is Ronald Reagan and his Dragon is John Hinckley Jr. After Taurus shoots the former, the latter is set up to take the fall. Although this event actually took place the previous year.
Tomb Raider does this quite a bit. Atlantis was ruled by alien gods and King Arthur's Excalibur was a supernaturally-powerful weapon. A shard of Excalibur was later used by a Crusader. The rebooted games, from Legend onwards, establish the idea of the "monomyth", that all the legends and folklore of the world can be traced back to a "single remnant of the ancient world".
In Amnesia: The Dark Descent, Heinrich Cornelius Agrippa is found alive and trapped in an extremely aged shell of a body, kept alive by magic. An optional side-quest allows you to rescue him, and is required to be done for the 'good ending'. Johann Weyer is a character that's mentioned and heard, but never met in person, he's implied to have been a pupil of Agrippa.
The Shinsengumi were an interesting enough group on their own, but in Hakuōki they're secretly used by the shogunate as a testbed for a mysterious elixir which turns those who take it into nigh-unkillable but unstable and bloodthirsty superhumans. In addition to adding intrigue and a degree of uncertainty to the Foregone Conclusion, this also provides a convenient device to allow characters like Keisuke Sannan, Heisuke Toudou, and Souji Okita to remain involved in the plot well beyond the points at which their real-life counterparts died.
Dresden Codak has some interesting theories about notable scientists/psychologists/etc. One of the more notable examples suggests that Niels Bohr was a cat, and thusly, by Schroedinger's principles, is immortal, so long as he remains unobserved.
Homestuck: Colonel Sassacre (who is a Mark TwainExpy) raised young Nanna Egbert and was killed by a baby pistol-wielding Grandpa Harley. Oh, and Betty Crocker, instead of being a brand image, is actually a ruthless alien queen.
Jesus Christ In The Name Of The Gun is about Jesus getting fed up with God's "let's watch and see what happens" attitude towards all this suffering going on down on earth, so he kick-starts the Second Coming a little early so that he can go out in the middle of World War II and fuck up some Nazi shit. Ernest Hemingway comes along to give him a hand, and he needs it, because Hitler is a werewolf. Ethan Nicolle drew it.
The entire Dungeons and Dragons game in The Word Weary is based off of this idea- the characters play D&D characters in a version of the 1917 Russian Revolution in which Rasputin is a high-level cleric, the Tsar is a white dragon (and the Tsaritsa is a half-dragon) and most of the Tsar's supporters are Hobgoblins.
In Unwinders Tall Comics, Barbecue Sauce writes "Tesla fics", in which various heroes from history and fiction are revealed to actually be an immortal Nikola Tesla in disguise. Supposedly, Tesla fics are popular enough to have entire websites devoted to them.
In Dracula The Unconquered, it's revealed early on that "The Black Death" was actually a euphemism for Dracula himself, and the millions of deaths were caused by vampires rampaging across Europe.
In lonelygirl15, Aleister Crowley was a founding member of a secret society which aimed to gain eternal life by draining the blood of the legendary descendants of the Egyptian goddess Hathor.
That's actually probably the most likely thing mentioned on this page.
New Vindicators features an immortal Isaac Newton as a recurring character, as an Esper (normal person with psionic powers) able to listen to spirits who drank an elixer to make him immortal. He's also a genius even beyond his real world self, having built sophisticated androids, and is part of the world's Illuminati along other immortal types. Ambrosius Aurelianus, a real life historic Romano-British warlord, is also the mythical King Arthur and his time's own Aurelius-which is to say, master mage.
In The Salvation War Dante's Inferno is an accurate portrayal of Hell based on visions sent to him by demons.
George Washington "had a pocket full of horses, fucked the shit out of bears, threw a knife into heaven, and could kill with a stare!"
And JFK was a telepathic, zebra healing, flying robot.
In James Potter And The Hall Of Elders Crossing, they reveal that the headmaster of the American version of Hogwarts (or one of several, it is not clear how many wizarding institutions America has) is Ben Franklin. Yeah, apparently the coolest Founding Father was also a wizard, and has a machine that has slowed his aging so much he's still alive.
In Fate Nuovo Guerra, it was said that Archimedes was actually a magus, and the legend about him using mirrors to burn a Roman fleet was actually a heat beam spell that he created, the Heliocaminus.
The Real Ghostbusters: Alexandre Gustave Eiffel is discovered to be a 19th-century ghost hunter, and the prominent French landmark which bears his name turns out to be a primitive ecto-containment system.
Men In Black The Animated Series states that Martin Luther King Jr. John Lennon, and Raffi were human mecha powered by the tiny, peace-loving Arquellians. Presumably, they haven't dabbled in Earth politics for quite a while.
There was a real Macbeth, although he wasn't quite the power thirsty regicidal dude depicted by William Shakespeare. In Gargoyles, though, Macbeth is a Highlander-style Immortal, still alive today thanks to an immortality pact. Word of God states that he and Shakespeare were drinking buddies, and that he was amused by the play named for him.
The Duh-Vinci Code reveals that Leonardo da Vinci is still alive because he's from a race of long-lived Human Aliens and actually the dumbest person on his home planet, coming to Earth as he'd be far smarter in comparison.
An episode of The Tick features several major historical figures transported through time to the present. When the historical figures are all captured and tied up by the bad guys, George Washington Carver (who is among them) utters the immortal words, "If only I could get my hands on those peanuts!" He eventually does, and turns them into weapons of mass destruction.
Family Guy. Lou Gehrig created the disease bearing his name to take over the world.
And Charles Lindbergh accidentally flushed away his son when he was teaching him how to use the toilet, then got rid of Amelia Earhart because she had seen too much.
A classic Rocky and Bullwinkle arc involved the Kerwood Derby, a hat that made its wearer the smartest person in the world. Supposedly Einstein was wearing the Kerwood Derby when he developed his Theory of Relativity, and Archimedes wore the derby in his bathtub when he discovered his theory of water displacement (or at least remembered where he left the soap). According to the narrator, it was worn by Alexander the Great when he conquered the world, by Philip of Macedonia when he conquered the world, and by Elvis Presley when he...well, you get the idea.
Time Squad is all about secret historical weirdness, Hand Waved by history becoming "unstable" as it "ages". This apparently leads to stuff like Ludwig van Beethoven becoming a professional wrestler, Eli Whitney inventing flesh-eating robots instead of the cotton gin, and Albert Einstein giving up his work as a physicist to take on the identity of a boisterous used-car salesman.
The founder of Gravity Falls, according to the episode "Irrational Treasure", was Sir Lord Quentin Trembley III, the 8th & 1/2 president of the USA. He was the most ridiculous president of the US, and was kicked out of office and erased from the history books. His term was replaced by William Henry Harrison (the official 9th and thus why Trembley was 8th & 1/2), and the government claimed some waste shoveling village idiot was the founder of Gravity Falls. Oh, and Ben Franklin was secretly a woman.
Codename: Kids Next Door reveals astronauts never landed on the moon, they just thought they did. The KND hacked the transmission and sent them to a fake moon so the adults wouldn't find out about their Moonbase. Also, according to a tie-in comic, the Great Wall of China was built to be the world's biggest water slide.
The film The Guardians of the Lost Code reveals that the fall of great ancient civilizations and ancient wars of conquest were driven by The Dark to eliminate the brijes and obtain the synchronicity. The last instance of this was the conquest of the Americas, in which we see Hernan Cortes under orders of The Dark torturing the last Aztec emperor Cuauhtemoc for the secret of the synchronicity.