In General
- Channel Hop:
- The series moved from Cartoon Network to Adult Swim's Toonami block, with Williams Street now producing the series alongside Cartoon Network Studios. Because of this, the entire series's run and property is now considered part of Adult Swim.
- The first four seasons were animated by Rough Draft Studios. The fifth season was entirety animated by Digital eMation with the exception of XCVIII, which Rough Draft animated.
- Creator Backlash: After the show moved to Adult Swim for its fifth season, it's been reclassified as an Adult Swim show completely, even the original four seasons. As a result, Cartoon Network has rarely ever talk about the show on air or on social media and its likely they never will again.
- Creator's Apathy: Part of why the movie never happened was because the crew was burned out after making the show for four straight years and felt that they were too creatively exhausted to give the series the ending it deserved, deciding it was more respectable to leave it open ended. They were unaware, however, that picking it up again would take as long as it did.
- Celebrity Voice Actor: In the Japanese dub, Aku is played by the late Bunta Sugawara, best known as Kamaji in Spirited Away and Shozo Hirono in Battles Without Honor and Humanity, while Jack was voiced by movie actor Takashi Ukaji, who voiced Raoh in the Fist of the North Star films and the Legends of the Dark King TV series.
- The Danza: In episode XIII, Phil LaMarr voices a young boy named Phil, who performs an extremely dead-on imitation of Jack himself.
- Executive Meddling: Cartoon Network executives decided not to risk spending money on another movie that might not break even after the mixed reception and poor ticket sales of The Powerpuff Girls Movie. They did offer to extend the show for another thirteen episodes (a full season), but Genndy declined and let the original series finish out its 52-episode contract.
- Fake Nationality: Samurai Jack and Ashi, two Japanese characters, are voiced by Afro-American Phil LaMarr and Caucasian Canadian-American Tara Strong, respectively. Otherwise averted with most of the other Japanese characters, however, who are all played by actors of East Asian (though not always Japanese) ancestry.
- Fake Scot: John DiMaggio, an American, voices the Scotsman, who is of course Scottish.
- Kids' Meal Toy: Subway had a set of five toys in 2002. There were boxing figures of Jack and Aku, the Minion Buster, the Aku Popper, and Jet Jack.
- Reality Subtext: This show about traveling one thousand years into the future debuted in 2001 amidst cultural excitement and anxieties over The New Millennium.
- Referenced by...: Samurai Jack make a cameo in this song
. - Screwed by the Network: When [adult swim] announced that the original Samurai Jack would return to Toonami, its timeslot was not revealed until a couple weeks before its airdate, when it was revealed that it would air at 4:00am. Granted, Samurai Jack was an old show at this point, though considering that (1) Samurai Jack hadn't aired on Toonami for about six years, (2) it was replacing FLCL—a show that was older than Samurai Jack, had been rerun into the ground on [adult swim], has only six episodes compared to Samurai's 52 (not counting the revival), and was airing at 2:30am because it was Adored by the Network—and (3) 4:00am is the deadest hour of the night (one usually reserved for reruns), it was still very disappointing. This did not stop the new season from being greenlit, however, so it clearly did well enough for the network's tastes. Averted with that new season as it was heavily promoted and aired at the very beginning of the block.
- The show itself vanished entirely when the City Era arrived and the last 4 episodes didn't air until August of that year, taking 9 months to air when related to the prevoius episode "Jack Vs. Aku", which aired on November 2003.
- Schedule Slip: When the new season was announced in December of 2015, the announcement was accompanied with an admittedly vague premiere date of "late 2016". The show finally received its official premiere date (11 March 2017) two months before that airdate.
- Sequel Gap: The show's original run ended in 2004. After a comic book continuation by IDW Publishing ran from 2013 to 2015, the show's final season was announced in late 2015 and began airing in 2017 (nearly thirteen years after the original show's run ended).
- Shrug of God: Genndy admitted that he never gave much thought to some of the characters' names, up to and including Jack himself, whose real name is never revealed. When asked what Jack's father's name was, he simply replied "Emperor."
- Word of Saint Paul: This is defied in one respect: Phil LaMarr said he was regularly asked between 2004 and 2017 if Jack would ever make it home. He would respond along the lines of "that's above my pay grade".
- Writer Revolt: After having done two dialogue-heavy shows with Thick-Line Animation, Genndy wanted to do a show with neither.
- Write What You Know: Storyboard artist Brian Andrews is well-versed in actual martial arts, being a practitioner of Chinese wushu. It clearly shows in the animation.
Season 5
- Acting for Two:
- Grey DeLisle voices the High Priestess and the Scotsman's Daughters. She also voiced a good amount of characters during the original run of the series.
- Tara Strong voiced Ashi and most of the daughters of Aku. She also voiced many characters during the show's early years.
- Adored by the Network: It gets rerun by [adult swim] a lot, with frequent back-to-back episodes and marathons even well after it finished its run.
- Approval of God: Sort of. According to Greg Baldwin, Mako's daughter sat in on a recording session during season 5. When he was done, she hugged him and said "It's like he was back." Baldwin still doesn't think he gives a good impression of Mako, but he did say he was proud to give that moment to her.
- April Fools' Day: The fourth episode of Season 5 was pre-empted on April Fools' Day 2017 on American airwaves. In its place was the unannounced Season 3 premiere of Rick and Morty, which ran on a four-hour marathon loop prior to midnight (and the rest of Toonami running as usual).
- Channel Hop: Kind of. While [adult swim] is, strictly speaking, simply Cartoon Network's nighttime block, the two are usually treated as separate entities altogether. This makes Samurai Jack the only series to air new episodes under both the Cartoon Network banner and the [adult swim] banner.
- In the UK, [adult swim] was on Fox instead of Cartoon Network during the season's run, so it aired there.
- Accordingly, the original run of the series was re-labeled under the [adult swim] banner on all media since 2017, since its status as a kid's cartoon has apparently been irrevocably tarred by the content of Season 5. As a result, the whole franchise has become a property of Adult Swim instead of Cartoon Network.
- Creator Backlash: While he enjoyed voicing the character, Greg Baldwin has admitted that he felt his take on Aku "sorta sucked" compared to Mako's original voice. Specifically, he felt he couldn't match Mako's ability to utilize Mood Whiplash for Aku's comedic and frightening sides.
- I Want You to Meet an Old Friend of Mine: Phil LaMarr and Keegan-Michael Key were both previously cast members on MADtv (1995).
- Meme Acknowledgment: Greg Baldwin is aware of the "EXTRA THICC" meme.
- The Other Darrin:
- As Mako died in-between seasons, Aku is voiced by Greg Baldwin, who likewise took over his role of Iroh in Avatar: The Last Airbender and first did Aku's voice in FusionFall (which also makes this a Role Reprise).
- Keegan-Michael Key voices Da Samurai in "XCVII", when he was previously voiced by David Alan Grier.
- The now-old Olivia is played by Grey DeLisle instead of Kath Soucie.
- Odin is voiced by Aaron LaPlante instead of Richard McGonagle.
- Recycled Script: The premise of Jack becoming frustrated with his lack of progress and the perceived hopelessness of his quest was tackled in several episodes of the original series, in various ways, with various degrees of focus. The big difference here: the script is playing for keeps this time around, and the frustration is no longer transitory — it has become all-encompassing.
- Refitted for Sequel: There were plans for a movie that just had way too many false starts, so Genndy eventually reworked those plans into a ten-episode final season.
- Role Reprise: While it's a given that Phil LaMarr would return to voice Jack in season 5, less obvious is Greg Baldwin voicing Aku. While he's The Other Darrin to Mako, he did voice the character before in the FusionFall game, so it also qualifies as this. Later, John DiMaggio returns to his role as the Scotsman.
- Saved from Development Hell: Genndy originally wanted to end the series with a movie. Cartoon Network showed no interest after the failure of The Powerpuff Girls Movie, so Genndy spent the decade after the show's original cancellation pitching the finale movie to various studios. He ultimately decided to end the show with one last TV season on [adult swim].
- Sequel Gap: The fourth season aired in 2004. It took thirteen years before the fifth and final season.
- What Could Have Been:
- Cartoon Network offered to extend the series for another thirteen episodes, but Genndy Tartakovsky, exhausted from making the show for four years with no break and keen to start his own indie studio, opted to hold out for a theatrical feature instead. The eventual 2017 revival was a compromise.
- J. J. Abrams came very close to getting the proposed feature film off the ground. According to Genndy, it fell apart because Abrams' take on the story had too much plot.
- Genndy considered giving Aku an entirely new voice and explaining why after Mako passed away, but he decided to cast Greg Baldwin instead. The end result went halfway: Aku says in a Season Five episode that he is a "new" Aku, referencing both his voice (which is considerably deeper and more Slavic than Mako's reedy, Japanese-accented portrayal) and his new "beleaguered tyrant" characterization.
- "The Tale of X-49" was originally a lot more in line with the tone the show took in Season 5, but the fact that it was still topside of [adult swim] meant daytime censor hounds were entitled to police the show and object to allowing these scenes to air. This meant that Genndy may have planned for this level of violence and grit all along. It featured two deleted scenes, one where X-49 apparently capped a silhouetted figure and what looked like blood squirted out, possibly having grazed Jack or hitting one of the deactivated robots in the factory they were fighting in. The episode also featured the first chronological inclusion of profanity (courtesy of Daran Norris) that was cut from the finished episode, as after Lulu was kidnapped, X-49 said, "Damn feelings." See it all here (the voice acting doesn't come in until the last piece of deleted material). It makes the episode feel even more inspired by the futuristic/spaghetti western/film noir tale of Cowboy Bebop, which includes its own fair share of guns versus swords, and is a series Daran Norris has also lent his voice to when the movie was dubbed into English.
- Write What You Know: Jack's Beard of Sorrow was based on the kind of beard Genndy would grow out whenever he and his wife went camping.
- Write Who You Know: Genndy based Ashi on a childhood crush.
