Also, Raoh and The Dragon Ryuuga for those under Raoh's dominion: he may be the Big Bad, but he protects his subjects from raiders and bandits. Best shown when he was believed dead, and his troops in two villages started brutalizing the civilians: in one, people was in despair until Ryuuga started killing the mutineers (note that Kenshiro was there, and people was still desperate); in another, Raoh shows up, and people start cheering, while the mutineers, after their boss got his head slapped off, kneel to receive their just punishment (death by stomping from a giant horse).
Lelouch Lamperouge in Code Geass - before he entered the scene, the Japanese La Résistance was weak, divided and didn't have a chance at defeating Britannia's army. Zero managed to not only create a force that the oppressing army in Japan had to reckon with, but during the course of the series formed an alliance against Britannia with every single free country in the world. At the end of the series, Lelouch specifically invokes this trope - only with himself as the evil emperor and Zero (actually his ally Suzaku) as the Hope Bringer.
Tengen Toppa Gurren Lagann started with humans forced to live underground by an army of Beastmen with Humongous Mecha, who were slaughtering every single person they found on the surface. Then Kamina managed to create the Dai-Gurren Brigade, the first real La Résistance. And when he died, Simon took his place and led them to the victory over the Beastmen and their master.
Mobile Suit Gundam - Amuro, with his Gundam, was a factor who helped balance the odds in the war between Zeon and Earth Federation. It was later retconned by saying that his Gundam wasn't the only one used in that time.
At the end of Higurashi Kai this trope is discussed when Rika says that the only world when they managed to defeat Big Bad was one where Hanyuu was a real person, not a ghost. Also, Keichii did do wonders to her resolve.
In Sailor Moon, it's the title character herself. She inspires other people to fight on despite the apparent hopelessness of the situation.
Princess Tutu's titular character, whose Dance BattlingWarrior Therapy either gets her opponents to return the prince's heart shards or stop before sacrificing their own hearts to the Raven. It is eventually revealed that Princess Tutu's pendant was the prince's last heart shard, the shard of hope. However, even after giving up the heart shard, Ahiru becomes a symbol of hope to everyone in the story, and her actions help Mytho to finally defeat the Raven once and for all.
Attack on Titan has Eren Yeager, a human with the ability into a Titan. Many people see him as the only viable weapon against the titans. He is responsible for the first victory humanity has had in over a century of fighting. As of chapter 50, this goes even futher when he gains the ability to control normal titans
V from V for Vendetta - nobody could ever dream of standing against the government, but apparently they forgot to tell him that.
Not surprisingly this is part of the job description of the Blue Lanterns who literally channel the power of hope. The relatively few people who can "inspire great hope" has limited their membership quite drastically.
Batman is perhaps the only reason anyone with an ounce of sense stays in Gotham City. The sheer impact of Batman's presence can become a tide turner in much grander battles, as well: in Kingdom Come, Batman's arrival (almost) brings victory to Superman's faction in the climatic Battle of Gulag, as The Narrator points out.
Captain America of course. He especially became this for the fractured and extremely distrusted Marvel superhero community when he returned to life during Dark Reign.
The protagonists of Children of Men, and specifically the young mother with her baby, are this for the entire world, as no one has given birth in nearly 20 years. Near the end of the movie they stop a shoot-out between the army and some terrorists by simply walking nearby.
Jakob from Jakob The Liar ultimately serves as a deconstruction of the trope. Set during the 1940's during World War 2, Jakob fills his fellow Jews with hope over news that the Russians will soon liberate them from the Ghetto, telling them he got the information from his "secret radio." In truth, while the initial news is true, it eventually snow balls into him having to fabricate news to keep up the charade. This torments Jacob because his new found status puts him at risk of being arrested by German soldiers, but at the same time his lies actually give the Jews inspiration to live on and suicide rates drops.
Paul Atreides/Muad'Dib in Frank Herbert's Dune. Or he was a cynical Manipulative Bastard who used his charisma to get primitive folk to follow him, took over the universe by threatening to destroy it and forcing a princess to marry him whom he intended from the start to treat dreadfully. Preceded by Imperial Planetologist Pardot Kynes, who gave the Fremen the idea that bringing water to Arrakis was possible in the first place.
King Akio feels this about Sato in Forbidden Book. Unfortunately he's the only one who feels this way.
Olórin, aka Gandalf, is a LITERAL Hope Bringer. It's said in The Silmarillion that whenever he walks among Men or Elves, he inspires hope and courage. Unfortunately, his tendency to come to people when things are about to go wrong is often misunderstood, giving him the reputation as a "Herald of Woe." The Valar make Eärendil into one of these after he completes his epic voyage to Valinor. They turn his ship into a flying boat, and he is tasked to sail the skies forever carrying the Silmaril, appearing as a star of hope to all in need of it.
Aragorn was even named Estel at birth: the Elvish word for "hope". This makes him a literal as well as actual hope-bringer.
Kelsier in the Mistborn books is a rather extreme example in that he set himself up as a martyr specifically to inspire hope in the downtrodden Skaa populace. He even informs the Lord Ruler at one point that he is hope.
In The Hunger Games trilogy, Katniss Everdeen (and President Snow...) eventually realizes she has become this to the Districts, the spark that finally leads to actual uprisings and full-scale rebellion.
In Those That Wake, Laura is this to Mal. By the end of the series she becomes this for the world.
Revolution: Charlie's actions lead to the slaves being freed in Episode 2, La Résistance getting an advanced weapon (a sniper rifle) in Episode 3, children being rescued from indoctrination by the Monroe Republic in episode 7, her brother Danny finally being rescued in episode 10, and a scientist and his family being saved and released in episode 16.
In the animated video for Disturbed's cover of "Land Of Confusion", their mascot, The Guy, managed to turn people, who were previously running away and hiding from evil soldiers, into an angry mob who beat the hell out of their former oppressor, attack ONZ headquarters, punish corrupted politicians and bind the Anthropomorphic Personification of Greed, who is then killed by The Guy.
Moses in Peter, Paul and Mary's "Man Come Into Egypt."
Lots of top faces have played this role, notably Hulk Hogan, Sting and John Cena.
Halo: John-117, and to a lesser extent, all the other SPARTAN-IIs. The Elites (and later the Brutes) are this for the Grunts.
Half-Life: Gordon Freeman does one better. He is seen basically as the second coming by Half-Life 2 (the little bible references like Judith Mossman betraying him (Judith is the female form of Judas) don't help stopping it).
Harold from the same game is weary of his existence bonded to a tree and wants to die. You can convince him to live by pointing out that he is a Hope Bringer to the Tree-minders thanks to the greenery he is producing.
Some see Commander Shepard as this in Mass Effect. Paragon Shepard is an indisputable example of this trope. It helps that s/he's such an extreme Magnetic Hero.
Hackett: You can pay a soldier to fire a gun. You can pay him to charge the enemy and take a hill. But you can't pay him to believe.[...] When you went up against Sovereign, there was no good reason to believe you'd win. But your crew didn't seem to care. They went along anyway. Your trip through the Omega-4 relay? That was a suicide mission if there ever was one. Yet there your crew was, standing beside you, proud to serve. Why? Because they believed in YOU, their leader!
Mario is frequently seen as this. Sometimes, Princess Peach pulls this trope too.
You are this in the Ace Combat games, which most noticeably began in Shattered Skies. The radio chatter makes it very clear that everyone thinks your appearance guarantees a victory on your side.
From Shattered Skies as well, Yellow Squadron, more specifically Yellow 13, was this for the enemy.
The Grey Warden is seen as one of these by most of the populace in Dragon Age: Origins. Hawke becomes this for the Fereldan refugees, then later most of the population of Kirkwall, and possibly most of the now-rebelling mages of Thedas by the end of the sequel.
Link is frequently this in several of The Legend of Zelda games. Depending on the game, sometimes Zelda herself is too.
Diablo's Auriel is the Archangel of Hope, so this trope is natural to her - several characters, angelic or otherwise, have their spirits renewed once she is freed from Rakanoth's clutches.
Spyro in The Legend of Spyro series. The Dragons are on the verge of losing. Only Ignitus has escaped Dark Cynder's clutches, and he's left in a Heroic BSOD, hiding in a cave awaiting the end. Then Spyro shows up and gradually manages to convince everyone the war can be won.
In Final Fantasy X the summoners act as bringers of hope as they go on their pilgrimages in a bid to defeat Sin and bring about the Calm. Unfortunately, it's a false hope since the Final Summoning that is used to slay Sin also ensures its rebirth. Yuna rejects this once she finds out the truth and resolves to find a real solution.
In the sequel, Yuna is even more so. Everyone knows that she is the bringer of the Eternal Calm- something once believed, with good reason, to be impossible- and most are in awe of her. When Vegnagun is threatening Spira, it is Yuna who convinces others to travel to the Farplane and fight it.
Raidou Kuzunoha vs. King Abaddon has the titular character, who through constant fighting to protect the Capital has become a potent symbol of hope. It's due to this that Shinado's Anger, a divine aspect of despair, continuously faces and taunts him to drop his title and duties, as they inspire too much hope for him to triumph. When that fails, Shinado's Anger starts dispatching assassins, which only further weaken him as they fall, strengthening Raidou and the people of the Capital's faith in him.
Shin Megami Tensei IV's Main Character becomes this in the Neutral Route by helping as many people and demons as he can both in Tokyo and the Eastern Kingdom of Mikado, to the point of recreating one third of a divine entity's power by the sheer amount of hope he inspires. Then he proves why he can generate so much hope by taking back the other two thirds from the Seraph Merkabah and the Demon Lord Lucifer. At the end of the Neutral Route, the people of Mikado believe so much in him that they are ready to evacuate their kingdom at his command. The Hope Crusher White are utterly furious at him, as they wanted to break his spirit so he would never again seek any form of renewal or continuity, and keep throwing divine monsters and even Alternate Timelines in his path - fat lot of good it did to them.
BlazBlue has its own in the form of Makoto Nanaya, whose presence in Kagutsuchi in Continuum Shift reinvigorates those who know her best to varying degrees. To drive the point home, her own Story in Extend is titled Slight Hope. Examples include improving Noel's mood in Desperation and instilling true courage in her in the month between Continuum Shift and Chronophantasma, causing Jin to stop thinking about his brother in proximity to her in Decision (though this wasn't the only force at work), and renewing Tsubaki's spirits in Slight Hope- the choice to interrogate Hazama after this last act caused Rachel to go out of her way to save her when Hazama's patience finally expired.
Dangan Ronpa has Makoto Naegi, who is pretty much the most optimistic member of the school and always tell people to never lose hope, even if Monobear has been pushing them to just fall into despair already. He succeeded, making everyone stop playing Monobear's game of murders, and his title changed from 'Super High-School Level Good Luck' into 'Super High-School Level Hope'. A contrast from the Big Bad, whose title is 'Super High-School Level Despair'
Kingdoms of Amalur: Reckoning has you what with being Immune to Fate. Fateweavers treat you like Jesus and people you help say they're happy to have met you. Considering how most quests would have ended had you not appeared, it's clear that Amalur was very, VERY, VERY close to becoming a Crapsack World.
Aatrox from League of Legends invokes but subverts this trope for the sake of increasing his power and sating his bloodlust; His appearances in history have him come and aid the losing side of a war by fighting back the enemies by himself and rallying them under his power. However, he brings too much hope and eventually the formerly losing side turns the war from a counterattack to a massacre in which the individuals often don't realize how far they've gone until they're staring at the corpses of the enemy sides' innocent civilians.
The (translated) lyrics to the title song for The Elder Scrolls V: Skyrim play up the Dragonborn as this. The bard song "The Dragonborn Comes" does as well. A sample of the title track:
Dragonborn, Dragonborn, by his honor is sworn, To keep evil forever at bay! And the fiercest foes rout when they hear triumph's shout, Dragonborn, for your blessing we pray!
Pharaoh City in Lightbringer was a Crapsack World ruled by a gang known as the Slavers. Things had gotten to the point where they were able to kidnap and sell anybody including police officers and their families. When the titular character became a superhero, his first mission was to bring the gang down - which he did.
The protagonist Asher Walters in The Chronicles of Utopia is the Knight-Errant of Furyondy and one of Veluna's best generals. Rising through the ranks during the two world wars against the Big Bad he manages to to turn the tide and ultimately defeat the massive army of darkness poised to wipe out all life on the planet, though it does require the help of the gods in the end to pull it off.
The Gungan Council has Bethany Kismet and Eden Kisori both acting for the inspiration of their respective groups of Jedi. While Beth frequently gave reason for pacifist Jedi to believe they could change the galaxy, Eden rallied more aggressive Jedi and inspired them to launch a crusade against the Sith and Empire.
In Worm, Scion is this, as depicted in his Establishing Character Moment. An Endbringer is attacking Brockton Bay, and killing hundreds. Every parahuman for miles has shown up to fight it. Even the villains have established a truce to fight this Omnicidal Maniac that threatens them all. And then Scion arrives, and the despair that lifts off everyone at this is palpable. This trope is horribly subverted in the plot's finale, though.