The Marine that Jango hypnotized into thinking that he had captured Captain Kuro went on to become Captain Axe Hand Morgan, one of the first villains in the series.
Whitebeard's full name is Edward Newgate. Blackbeard's full name is Marshall D. Teach. If you take Whitebeard's first name and Blackbeard's last name, you get Edward Teach, which is the historical Blackbeard's real name. On a related note, Oda has stated the discovery of one of Blackbeard's ships was what inspired him to make a manga about pirates.
Thatch, Whitebeard's 4th Division Commander, and the guy who Blackbeard killed for the Dark-Dark Fruit (Yami Yami no Mi), is based on an alias the real-life Blackbeard used.
The way Luffy activates Gear Third, by putting a thumb in his mouth, biting into the joints, and blowing to inflate his arm's bones, is visually similar to one of the more common ways Popeye the Sailor would bulk up after eating spinach.
Given that Franky's character design is 50% Popeye with 50% Jim Carrey, this was likely intentional.
His Gear Fourth activation is similar to Eren Yaeger biting down on his arm to activate his Titan from Attack on Titan.
In one SBS column for Volume 56, Oda answered where each of the Straw Hats would live in the real world:
Gecko Moria is the tallest (22'8") and oldest (48) out of the original Warlords of the Sea, while Hancock is both the youngest (29) and shortest (6'3 and a half, or 191 centimeters).
After the time-skip, Trafalgar Law's 26 makes him the youngest Warlord, and Hancock, at one centimeter shorter than Buggy's 192, remains the shortest.
One Piece was originally only supposed to run for 5 years. Oda has admitted that one of the reason it has become such a Long Runner (passing such luminaries as Dragon Ball and InuYasha) is that he simply enjoys writing it.
Oda based the concept of One Piece on a vision of manliness, since Dragon Ball already did everything a kid could be happy about.
Not many people know of Singapore's English dub, done by Odex. Not even Singaporeans. Mainly due to the fact that it only did the first 104 episodes. Even fewer people know that Odex got their license before4Kids Entertainment did.
Contrary to what some believe, the word "Nakama" CAN and DOES translate to English quite easily. The direct translation is "comrade". It can also mean "crew(mate)", or "friend", or True Companions, or "bosom buddies", or etc., even if those words aren't as exact a match as "comrade" is. In short, if anyone tries to say that "Nakama" is a special word that cannot (and must not) be translated, they're either unaware of that or lying.
The character of Cat Viper was based on a song that Cho had made up, called "Let's go see the Cat Viper". It impressed Oda so much that he decided to include the character and the song in the series (Brook can be heard singing the song at a few points in the Zou arc).
Accidentally Correct Writing: Shortly after the flashback about Corazon, Doflamingo's brother who wears a black version of his iconic pink coat, scientists discovered this.
Acclaimed Flop: In the U.S. and Latin America; in Japan, it is by far the most popular franchise since Dragon Ball. Part of this is because One Piece is far more "cartoonish" than the popular anime franchises such as Naruto or Bleach (which seems to be a turn off to some of the hardcore set thinking it a children-oriented series). The other part is that the first attempt to have One Piece breach American audiences was the 4Kids dub, which alienated quite a few potential fans and the company's naysayers for years — only now, almost a decade after 4Kids dropped the license, has the franchise managed to recover from the blow and gain a solid foothold in America. A second and more recent blow, however, is some arcs to dragging their feet. Viewership of the show declined and sank with the uncut Funimation Toonami run of the series, as did the fact they only got the licensing rights at a weird point in the series after all the pre-HD episodes and the series itself was nearly a decade ahead, so neither first-time viewers nor veteran viewers got their appropriate fix and the block ultimately dropped the series after the Thriller Bark Saga.
Adored by the Network: Done for Toonami in the United States. When the show's infamous 4Kids dub switched over from 4Kids TV to Toonami's lineup, it brought in favorable ratings for the early teenager demographic. When the 4Kids dub reached its end, Funimation produced the dub and the series became a favorite all the way to the end.
Kazuyuki Sogabe, the original voice of Ben Beckman, was diagnosed with cancer and he retired after that, so Aruno Tahara took over for his later appearances. Sogabe later died from the disease in 2006.
Mihawk's VA Takeshi Aono suffered a stroke in 2010 and Hirohiko Kakegawa voiced Mihawk for all later appearances. Complications from Aono's stroke would later take his life in 2012.
Ginzo Matsuo, Smoker's original voice actor, died of cancer in 2001. Mahito Oba would replace him as the voice of Smoker.
Daisuke Gori, the voice actor for Dorry, Rockstar and Jimbei, committed suicide in 2010. Katsuhisa Hoki replaced him as the voice of Jimbei.
Takkou Ishimori, Sengoku's VA, passed away from heart failure in 2013 and Toru Okawa voiced him in his Time Skip appearances.
Goro Naya, the voice of Crocus, passed away in 2013 due to chronic respiratory failure, though he currently has no replacement as the character has not had any voiced dialogue since. His younger brother Rokuro Naya, voice of Haredas, died a year later and also has no replacement for the same reason.
Koji Yada, Zeff's original VA, died of chronic renal failure in 2014, so Ben Hiura replaced him for his later appearances.
Chikao Ohtsuka, Gold Roger's VA from the very beginning, passed away from ischemic heart failure in January 2015, so Masane Tsukayama replaced him for further appearances.
Kazunari Tanaka, who provided the voice for Talaran, Avalo Pizarro, Brownbeard, Manboshi and Blackback, died in October 2016 due to intracerebral hemorrhage.
Hiromi Tsuru, the voice of Shakky, died in 2017 of aortic aneurysm, so she will be replaced for further appearances. She has been recast by Masumi Asano.
Unshou Ishizuka, who voiced Kuina's father, Kizaru and Kong, died of esophageal cancer on August 13, 2018. As such, his roles will be recast.
Tetsuo Goto, the voice of Hannyabal, Saint Mjosgard, and Lao G, passed away November 6th 2018 from esophageal cancer. His roles will be recast.
Toshiko Fujita, original voice of Big Mom, died of breast cancer on December 28, 2018, although she had already been replaced by Mami Koyama due to her declining health.
Jerry Russell, the English VA for Crocus, died in 2013 from abdominal surgery complications, and he was later replaced by Burl Procter.
Cole Brown, Blackbeard's English VA, passed away in November 2016, his new voice actor has yet to be announced.
Ed Blaylock, Sengoku's voice actor in the dub, passed away in April 2017 of cancer and he will also be replaced. Tragically, this duplicates the circumstances of the death of his Japanese VA, whose last time chronologically voicing Sengoku before dying was Film Z; Blaylock died after dubbing the whole Marineford Arc and Film Z prior to that, essentially leaving the voice actor replacement having to happen at the exact same point when the character reappears in a flashback during the Dressrosa Arc. Perhaps there is a Sengoku voice actor curse...
Daniele Demma, Brook's original voice actor, died on November 6, 2017 after a serious illness.
Channel Hop: The (first) American dub from FOX to Cartoon Network. The series got higher ratings on Toonami, and they aired the remaining episodes of the 4Kids dub after 4Kids TV stopped airing it and let the license expire. Then Funimation picked it up and gave it a second dub that continued to air (although Cartoon Network still cancelled it, despite improving ratings). It's got a second chance with Toonami when they resurrected on [adult swim]. Though ultimately was cancelled on that block as well due to a variety of factors. It's unknown if the series will try again for a network broadcast.
Even though Eric Stuart still has fond memories of working on the 4Kids adaptation, he admitted years later that it was a show that should never air on network television, as was the case when 4Kids first aired it on Fox. He also publicly admitted at conventions that their adaptation was terrible.
Mark Kirk has stated in an interview with Anime News Network that 4Kids was absolutely dissatisfied with what they did to the anime, given how they were forced to accept is as part of their licensing deal.
Creator Breakdown: Apparently, the whole thing with Gold Roger, Ace, and Rouge was because Oda was worried about his new baby being born.
Everyone who's voiced Luffy and Chopper in the original and both dubs. Averted in the Singaporean English dub (done by Odex) where Luffy is voiced by Chuck Powers.
Sentomaru, with the result that the axe-toting sumo sounds like an old lady who smokes like a chimney. The dissonance is pretty wild, but at the same time works pretty well. It's averted in the Funimation English dub, where he's voiced by Greg Ayres.
The Danza: One of the oddest cases of this trope due to how rare the name is, Ryunosuke, the awkward-looking dragon created by Kanjuro, is voiced by Ryunosuke Yamaguchi.
Development Gag: The titles of chapters 1 and 601, as well as the fifteenth anime opening, "We Go", use the phrase "Romance Dawn", which was the working title of One Piece.
If Marty Adelstein hadn't gone to Universal Studios Japan's Premier Show and met with Oda to develop the Live-Action Adaptation of One Piece, the series would've never been made.
Oda has cut back on using vertical speech bubbles since it screws with translators.
Dueling Dubs: There are three extant English dubs for this series.
First, Odex Enterprises, who was hired for Animax, made a dub in 2003 for the Asian market; it lasted 104 episodes and was as is typical for Animax extremely close to the Japanese script, maybe too close. It was also infamous for constantly switching out actors (Nami alone had three different voices by the time it was done).
Next, 4Kids Entertainment dubbed it in 2004 for the North American market, which aired in the U.S. on 4Kids TV on Fox and eventually moved to Toonami on Cartoon Network. It technically covered the first 142 episodes, but the massive amount of censorship reduced that count to about 104. This dub may be the best-known to casual fans, but due to its extreme unpopularity with the dedicated fanbase and the 4Kids naysayers, it is increasingly difficult to find clips of it online, even extending to YouTube. The internet hivemind seems absolutely determined to purge it from existence.
Then, Funimation redubbed the series beginning in mid-2007 and stopping in late-2010 but restarting in 2012 and still in production as of 2017. The dub covers over 540 episodes (including the Time Skip) and is a faithful translation of the original.
Dueling Shows: With Naruto, Bleach and Fairy Tail. Along with One Piece, the former two are often referred to as the "big three" of Shonen. Now both the other two have concluded (Naruto has moved into a sequel, Boruto, essentially starting from the ground up again, and Bleach may or may not stay finished due to Tite Kubo being uncertain about what to do with the current ending after a bout of poor health and subsequently trying to wrap things up as quickly as he could), One Piece is basically "the Big One" (Fairy Tail, while popular in itself, and now also finished, just doesn't have the same history behind it).
My Hero Academia enjoyed breakout popularity that has slowly caused it to gain ground beside One Piece.
Due to the Unfortunate Implications of Whitebeard's flag (the fact that it looks like the Nazi symbol), Oda had to change it as per the higher-ups' request.
All Supernovas who were introduced in Sabaody Archipelago arc exist because of this trope. Oda had already planned the general outline of the arc, but his editor said that it needed more content to spice things up. A mere three hours later, Oda had created nine new character designs and drawn a rough draft for a new manga chapter.
When 4Kids acquired the license to the anime, they didn't want anything to do with it. However, Toei forced them to dub it until 4Kids could drop the license.
When Funimation acquired the license to the anime, they wanted Luffy to be voiced by a man. Toei wouldn't allow it, and Colleen Clinkenbeard was cast into her Star-Making Role as Luffy. To be fair, Oda himself wanted a woman to dub Luffy, also.
Fandom Nod: The published lists of questions answered by the creator. Sometimes serious answers that add to canon, mostly humorous ones that... don't.
Also, when Luffy's Gum-Gum Gatling was voted the most popular attack of the series, its upgrade, Jet Gatling, was used to defeat the next Dragon-in-Chief.
Jimbei fans often call him Jinbae, a term of romantic endearment.
MANSOPP (all caps, no exceptions) for post-Time Skip Usopp. Following the label Doflamingo gives him during the Dressrosa Arc, this got upgraded to GODSOPP.
The crew that impersonates the Straw Hats after the Time Skip are referred to collectively as the Flawhats.
Sabuto. Sabo the character... plus Naruto's voice actress.
The alliance between Luffy and Law and their crews is frequently referred to as the Lawffy Alliance or the StrawHeart alliance, with the Heart and Straw Hat crewmembers collectively called the StrawHearts.
Throughout the Dressrosa Arc, a lot of characters with long names are given in-universe nicknames. Most notable are Doffy/Mingo (Doflamingo) and Cabbage (Cavendish). Naturally, the fanbase refers to these characters by their nicknames any chance they can get.
Fans have started calling the Vinsmoke children the "Eyebrow Rangers" due to their color-coded titles, high-tech weapons and suits, numbered outfits, and the fact that there would have been five if Sanji hadn't left.
After Chapter 903, "Big News" Morgan is now "Fake News" Morgan for his... exaggerated coverage of the event on Whole Cake Island.
Before Karasu formally debuted, he was seen in the form of his Devil Fruit powers as a murder of crows. He became colloquially known as the "crowzone" guy. This was the term people went with up until an expanded version of the scene with the crows from the manga hit the anime and his name got revealed as Karasu.
Some characters get jokingly referenced as having the Will of D by the fandom. These include Go D. Usopp and Buggy D. Clown.
It was speculated among the fandom for many years that Ace and Luffy were not blood related, despite a remarkable physical resemblance and matching personality traits. Eventually, this was confirmed, but then the Wham Episode came when Oda revealed who Ace's actual blood family was.
Was that Dragon and his revolutionaries skulking in the port the night after Sabo's boat got blown up? Yes it was, and Sabo is alive, has signed on with the revolutionaries, and is absolutely badass, just as predicted.
There were numerous fan predictions and fake spoilers of Blackbeard showing up with the Level Six prisoners during Whitebeard's war on the Marines. Sure enough, he did, but not when they thought, him stealing Whitebeard's power and with Avaro Pizaro either.
There was speculation that Charlotte Pudding, Big Mom's daughter and Sanji's arranged fiancee wasn't as nice as they seemed, despite helping the Straw Hats get to Sanji's location and the appearance of two of her sisters who were in perfectly arranged marriages and were willing to betray their colossal mother. It seemed to die down when they implied they were willing to die for the good guys, only to be revealed in the next chapter she was just pretending to be a nice girl and was evil all along (how evil? She tells Sanji's sister Reiju that she plans on killing the whole Vinsmoke family on Sanji's wedding day).
While on the subject, many fans had also speculated that Pudding was three-eyed girl who first appeared with Big Mom in Chapter 651. This was confirmed in Chapter 850.
Quite a few fans correctly guessed that there would be a live-action adaptation of One Piece.
Due to his Dub Name Change to "Dogtooth", it was speculated that Charlotte Katakuri was hiding an array of sharp, animalstic teeth beneath his cape.
104 episodes (144 episodes in the original) of One Piece with the 4Kids dub aired from September 18, 2004 to September 22, 2007, a couple of months after Funimation picked up the license. On the initial American television airings and American DVD releases, the 4Kids dub was intact on episodes #001-#104 (#001-#143) and #001-#052 (#001-#084). Re-releases of these particular episodes by Funimation were unedited and redubbed. Despite their ubiquity, it's becoming quite hard to find these days, especially since the DVDs of the first 52 episodes can be found cheap. So your best bet in finding the remaining 52 One Piece episodes with the 4Kids dub would be to trade with someone who recorded the show off of Cartoon Network during the aforementioned period it ran.
The same also holds true for Funimation's early dub when it aired from September 22, 2007 to March 15, 2008 on Toonami before the block's cancellationnote To the point where people on Reddit are classifying this dub as lost forever. On the American television airings, this early dub was intact on episodes #105-128 (#144-167). The Australian TV airings of #129-156 (#168-195) were aired uncut, so you would be completely out of luck finding those with the edited dub intact. What makes these episodes so unique are as follows:
1) In order not to be so radically different to the casual viewer, some of the 4Kids terminology (Zolo, Grand Compass, etc.) was kept in the dialogue.
4) When Funimation redubbed these episodes, in addition to using the correct terminology and so forth, subtle changes were made to the dialogue. Compare Colleen Clinkenbeard's first line as Luffy:
Luffy (Original Dub): You know what, that was a lot of fun, but I don't think we should ever go back there again.
Luffy (Redub): You know what, that place was pretty awesome, wasn't it?
Episodes 438 to 460 of the series with Norio Imamura as Ivankov aired from February 14 to August 1, 2010, before he was arrested for indecent explosure. Reruns and DVD releases have since replaced him with Mitsuo Iwata. Your best bet to getting the 22 episodes with Imamura as Ivankov would be to trade with someone who recorded the show off of Fuji Television during the aforementioned period in the run.
In a nod to the previous one, the Straw Hats Finally enter the second part of the Grand Line in Chapter 602
Mis-blamed: Confirmed in an interview with Mark Kirk, a former vice president at 4Kids who knew what happened, but didn't have anything to lose by making it public. To date, no one has disputed what Kirk said.
Here's the story - Contrary to popular rumors by fans and the company's naysayers, 4Kids never actively sought to acquire the show. The real reason it landed in their hands was because Toei Animationdesperately wanted to sell a license for their smash-hit cartoon to anyone who could air it on American TV.* At that point, One Piece had been on the air in Japan for over four years, and had recently hit in Europe and Asia, but nobody in North America seemed to want it.* It was revealed in a DVD commentary that Funimation was interested in the show prior to 4Kids getting the license, but they passed on it due to cost or, more likely, were denied it due to their inability to guarantee Toei a TV airing. Thus, when 4Kids paid a visit to Toei with the intention of licensing Ultimate Muscle and Magical Do-Re-Mi, they wound up being handed the One Piece rights in addition to the two series they were shopping for. They never watched a single episode before agreeing to the deal, and as the masters rolled in, they became increasingly shocked at what they'd gotten themselves into Toei's infamous Executive Meddling over the series couldn't have helped. Funimation have also mentioned this aspect of Toei in their commentaries. Notably, that Toei gets veto power over everything, and that they forced Funimation to cast a woman as Luffy, when they would have much rather cast a man. The result of all this was extreme overreaction on 4Kids' part (even by their standards), which led to the most notorious anime Macekre since Sailor Moon.
Going further on the Mis-blamed line, it has been pointed out multiple times by multiple people in the industry that Toei approved every single alteration 4Kids made to One Piece. Changing a gun into a spring-controlled mallet... thing? Somebody at Toei approved that. Digitally altering Laboon into an easily-destroyed iceberg to completely skip a rather important dozen-plus episodes of plot simply to get to the "cute" character more quickly (and causing severeplot holes had the show run for much longer)? Yep, somebody at Toei signed off on that too. The "One Piece Rap"? A Toei exec... well you get the idea.
Missing Episode: Material was cut in the original version of the short-lived 4Kids dub, mostly for violence, but sometimes smaller arcs were as well.
Commander Shepherd from one of the anime filler arcs. No relation to that other Commander Shepard.
An example in the same series: Scarlet, the perverted gorilla in Shiki's crew, and Scarlett, the former crown princess of Dressrosa and Rebecca's mother.
One member of the Usopp Pirates is a kid named Carrot, later on there's a Rabbit Mink that tags along with the Straw Hats named Carrot. The Japanese version averts this as Carrot of the Usopp Pirates is referred to as Ninjin (the Japanese word for carrot) and Carrot the Mink is actually called by the English word "Carrot", but the English versions play this straight.
Tsuru, the name of both a Marine Vice Admiral and the owner of a tea house in Wano Country.
For a long time, One Piece was one of the more teeth grindingly annoying instances of the UK getting absolutely shafted by Toei. Six years after Funimation's dub began, Manga Entertainment finally acquired the series in 2013.
The roles were reversed somewhat a year later, when seven of the movies were released in the UK without any word of a US release to date.
Most of the movies and several of the TV specials haven't made it out of Japan.
Neither of the spin-off series were released in North America, though One Piece Party did at least see an official French release.
According to Mark Kirk, 4Kids' adaptation of the series was the worst thing that ever happened to the company. The adaptation was never rebroadcast on television again after 4Kids stopped producing it in 2006. As of 2019, fifteen years after it was first broadcast, it still hasn't.
Eric Stuart (the narrator of the 4Kids adaptation) has also publicly admitted at conventions and interviews that he wasn't happy with how it turned out.
David Moo (the 4Kids voice of Sanji) said in an interview that he supposedly disagreed with the voice direction given to his character.
Due to Kazuyuki Sogabe's health issues and eventual death, Aruno Tahara replaced him as the voice of Ben Beckman.
After Takeshi Aono's stroke in 2010 and later death in 2012, Hirohiko Kakegawa voiced Mihawk for all later appearances.
Following Ginzo Matsuo's death from cancer, Mahito Oba replaced him as the voice of Smoker.
After Daisuke Gori's suicide in 2010, Katsuhisa Hoki replaced him as the voice of Jimbei.
Due to Kazunari Tanaka's death, Manboshi is now voiced by Yasuhiro Mamiya and Blackback is voiced by Sota Arai.
Brownbeard was initially voiced by Yasuhiko Tokuyama, who was replaced by Kazunari Tanaka in later episodes. However, in a similar way with Tanaka's death, Masashi Sugawara would replace him for later appearances.
King Riku Dold III was initially voiced by Masashi Hirose. However, due to Hirose's health issues, Banjo Ginga replaced him.
Due to Iemasa Kayumi's illness and eventual death, Toshiya Ueda voiced Cobra for his appearances during the Marineford arc. After Kayumi's passing, Hozumi Goda fully replaced him after the Time Skip.
Big Mom was voiced by Toshiko Fujita for her appearance in the Fishman Island arc; Mami Koyama replaced her for the Whole Cake Island arc onwards.
Due to Koji Yada's death, Zeff is now voiced by Ben Hiura.
Toru Okawa replaced Takko Ishimori as Sengoku since the latter's death.
Beginning with episode 849, Gold Roger is voiced by Masane Tsukayama, replacing the late Chikao Ohtsuka.
In Coby's first appearances, he was voiced by Leah Clark. By the time of the Water 7 arc, Micah Solusod took over the role.
Helmeppo was voiced by Troy Baker for his initial appearances, but has since been voiced by head voice director, Mike McFarland, who also voices Buggy, due to Baker being involved in union-only projects after moving to Los Angeles.
After Jerry Russell's death, Crocus is now voiced by Burl Procter.
Cole Brown, Blackbeard's English VA, passed away in November 2016, his new voice actor has yet to be announced.
Ed Blaylock, Sengoku's voice actor, passed away in April 2017 of cancer and he will also be replaced.
Due to Funimation severing all ties with Vic Mignogna after allegations came out against him, Sabo will most likely be recast in his future appearances.
The Other Marty: After Norio Imamura's arrest for indecent exposure, Mitsuo Iwata replaced him as the voice of Ivankov for reruns and DVD releases.
Much like with their Dragon Ball Z Kai and Dragon Ball Super dubs, Funimation covered a number of One Piece opening and ending songs. However, they only dubbed the first four opening songs and stopped dubbing the ending songs after the thirteenth. The most likely reason for this is that Toei started hiring popular Japanese pop bands to record their theme songs as well as using actual pop songs for their openings. This means that the cost to license the songs would be higher than usual and the Japanese artists would likely be against a foreign company dubbing their works.
Mirai Kokai, the fourteenth ending song, was skipped in the Funimation dub to to licensing issues. Instead, it was replaced Eternal Pose, the fifteenth ending song.
The reason Zoro's name was changed to Zolo in both the 4Kids dub and Viz Media's translation of the manga; his name was a homage to Zorro, which at the time One Piece was initially licensed, was the subject of a copyright lawsuit despite that property having fallen into the Public Domain years prior. 4Kids, Viz and (initially) Toei all agreed to change his name rather than risk getting caught in a lawsuit. By the time Funimation got the anime license, Toei decided this was no longer a concern, so their dub was allowed to use his original name, though Viz Media's agreements with Shueisha specifying that he be called Zolo still stands to this day.
Star-Derailing Role: This might have happened to David Moo after he voiced Sanji in the dub. Toei essentially forced 4Kids to dub the series against their will, coupled with fan ire against him for things that weren't really his fault, caused him to retire from voice acting. To this day, he maintains a steady career as the co-founder and bartender of the Brooklyn-based Quarter Bar. As such, he was the only main voice actor not to return forSlayers Revolution and Slayers Evolution-R, where he had originally voiced Xellos (although even in Slayers, an otherwise popular dub, Moo's performance was a bit polarizing). An interview with the Slayers voice director (Michael Sinterniklaas, who also took over the role) suggests that it was a decision made by the powers-that-be, and not a case of Moo leaving on his own. However, everyone else in the old One Piece dub still has at least some sort of career.
During the reunion arc, Nami and Usopp are hassled by the fake Straw Hats, all are voiced by the same voice actors of the real Straw Hats in both Japanese and English, though their voices are changed around. Interestingly enough, Eric Vale, who voiced Fake Luffy, provided the test dub voice for Luffy.
As a result of Daisuke Gori's suicide in 2010, Jimbei's role is now played by Katsuhisa Hoki, who is also the voice of Gekko Moriah. This means in their fight in episode 468, Hoki is doing both voices.
Teasing Creator: Oda has made a career out of this trope, but his biggest moment is going on his scheduled one week break right after chapter 784, where he revealed the existence of Gear Fourth.
4Kids Entertainment only dubbed the first 142 episodes (turned into 104) and they didn't finish the rest of the show. Funimation's initial Toonami dub was forced to maintain continuity with the 4kids dub, but even that didn't help finish it when it was pulled off Toonami for unknown reasons.
When Toei was shopping around for companies to dub One Piece into English, certain recording studios were asked to produce test episodes for Toei to view. One of the studios in the running to dub One Piece back in 2004 was Funimation, which was already working with Toei on Dragon Ball Z; they were originally considering Eric Vale as Luffy and Christopher Sabat as Helmeppo (hilariously enough, they would take on the roles of Sanji and Zoro, respectively). However, Funimation was not the only company Toei was considering they also apparently got a test dub from Blue Water Studios in Calgary, and there were plans for a test dub from Westwood Studios in Vancouver. Jillian Michaels (who voiced Shippo in InuYasha), once listed Nami on her resume. Unfortunately, all of those plans were nixed when Toei sold the license to 4Kids.
Funimation wanted a man to voice Luffy in their dub of the anime, but Toei and Oda nixed the idea.
Daddy Masterson was originally going to appear in the manga, but Oda nixed the story so that the Straw Hats would leave for the Grand Line in the 100th chapter. Instead, Usopp just buys his goggles off-page and Masterson's story is only seen in the anime, and is thus considered filler by those who do not know this.
Originally, CP9 were going to be much different: Kalifa was a black-haired creepy woman, Jabra was a swordsman called Jakeen, instead of Kumadori there was a Gorilla-themed brute named Apollo, and Fukuro was actually well-muscled instead of being a fatso. Furthermore, the battle layout was different, and included Zoro vs Jakeen, Nami vs Fukuro, and Usopp against Blueno, amongst various things.
Oda mentions that he had intended to have Brook join the Straw Hats before Franky as he always intended for Brook to join the crew, meaning that Thriller Bark would've happened before Water Seven. However, because Kazuki Yao's performances as Jango and Bon Clay were so well liked, he created Franky and had him join before Brook.
In the Enies Lobby arc, one line from Luffy to Robin was considered but eventually unused: "Robin! Keep laughing! There's nothing to be afraid of! I'm with you!"
For the Dressrosa arc, Oda had nearly thirty other names options for Rebecca, like Violet, Girasole, Akiria, Noir, Iris, Isbell, Fabula, Russian, Laura, Helianthus, Seneca, Juvenalis, Vineyard, Lambda, Amazonia and Shalom. Some of those options were considered for meaning "sunflower" in other languages, while other options became the names of other characters, like Violet (Rebecca's aunt's alias) or Russian (Senor Pink's late wife).
Nami was initially going to have An Axe to Grind as her main weapon. One of her early designs also featured her having scars, as well as a cybernetic-looking left arm and right foot.
Marguerite initially had a Zoan Devil Fruit, specifically the Neko Neko no Mi, Model Black Cat.
Kuma looked very different, and was supposed to have a steering wheel embedded in his head, until the steering wheel was given to Shiki instead.
Judge's early design looked very different, and he was initially named "Saint-Germain", with his Red Baron being "Count Karakuri".
Moriah was initially meant to be a pastor with a split personality, and looked nothing like his final design. Perona also used to be more like a silent princess-type character.
One of Nightmare Luffy's early designs is somewhat reminiscent of Freddy Krueger's, fittingly so considering the arc he appears in.
Brook went through several designs as well; one showed him alive with Lennon Specs, another as a more serious-looking skeleton with a bandanna and no afro, and yet another with a top hat.
Robin was going to have a technique called Face Fleur, which would have allowed her to duplicate her face. It was rejected almost immediately after it proved too creepy in practice.
Mr. 2's initial designs looked very different, he was named "Mr. Happy Birthday", and he had a female partner named Miss Obon.
Vivi was initially nothing more than an enemy, and her being a princess is the product of pure chance: one time, Oda drew Miss Wednesday with her hair down, which made him think she looked like a princess. Since he had already planned out the plot for the Alabasta arc, this gave him the idea of making her the princess of Alabasta, and the rest is history.
Write Who You Know: Whitebeard is based on an old pub owner Oda used to hang around, and Whitebeard's first line was actually something that man always said. Like Whitebeard, he too had medical problems (i.e. hooked up to medical equipment) and is now dead.
You Look Familiar: Wadatsumi bears a striking resemblance to Sanjuan Wolf. Many theories of a connection of race have abounded.