The sixth season of King of the Hill originally aired on Sundays at 7:30–8:00 p.m. (EST) on the Fox Broadcasting Company from November 11, 2001, to May 12, 2002.^[1][2]

The showrunners for the season were Jonathan Aibel and Glenn Berger, who took over from Richard Appel, the showrunner of Season 5 and co-showrunner of Seasons 3–4 with Greg Daniels.^[3][4] Aibel and Berger had worked on the show since Season 1, and took yearly trips to Texas to better understand the show's setting, as they were not native to the area.^[5] Shortly after becoming showrunners in 2001, Berger commented to the Los Angeles Times that, "my writing partner and I are both Ivy League-educated Jewish guys from the New York area", adding that, "for most of the country, it’s a really cool, smart show about people they know. For New York and L.A., it’s like an anthropological study."^[5]

Aibel and Berger departed in late 2001, as a result of unspecified tensions behind the scenes.^[6] Greg Daniels temporarily ran the show again following Aibel and Berger's departure. Daniels recalled that in the summer of 2001 he was tasked with making 1 to 2 minute syndication cuts for every episode, and said that re-watching all the episodes made him appreciate the show and inspired him to become closely involved again.^[7] Aibel and Berger would eventually be permanently replaced by John Altschuler and Dave Krinsky for Season 7 and beyond. Altschuler and Krinsky both originated from states in or near the U.S. South, unlike all the previous showrunners (with the exception of Mike Judge). Many Season 6 episodes were rewritten heavily after the animatics, to the point that Fox often announced plots that were different from the ones that aired.^[3]

"Bobby Goes Nuts" was the first King of the Hill episode to be done with digital ink and paint, although the opening sequence which appeared in every episode up until that point also utilized digital ink and paint. A nightmare sequence in the episode "Are You There God? It's Me, Margaret Hill" was later done with digital ink and paint this season, even though the rest of the episode had traditional cel animation. The show would not permanently switch over to this production method until the eighth season.

In November 2001, Hal Boedeker of the Orlando Sentinel gave the season opener "Bobby Goes Nuts" a positive review, and described Fox's programming that night as "highly uneven: a clever King of the Hill, a mediocre Simpsons, an amusing Malcolm in the Middle and a pointless X-Files." Boedeker went on to write, "the sixth-season opener of King of the Hill manages the considerable feat of being more diverting than The Simpsons, and it does it with one of the hoariest bits of humor: the kick in the groin."^[8] The New York Post's Austin Smith praised the season final "Returning Japanese" in May 2002, writing that, "the episode figures to be the best of the season finales the networks have in store this week – cleverer by far than this Thursday’s baby hijinks on NBC’s Friends and Will & Grace. Those plotlines sound as desperate as this Tuesday’s episode of Frasier, in which Frasier stumbles into bed with Roz."^[9] Smith noted that King of the Hill "wasn’t always easy to love at first, [but] today – six seasons later – stands out as one of the most creative and best-written shows on TV."^[9]

In his 2006 review for the DVD release, IGN's Tal Blevins labelled it "a great season with no real stinkers."^[10] Blevins praised the episode "Bobby Goes Nuts", commenting that it "includes one of the most memorable lines ever uttered on television."^[10] In his review of the Season 6 DVD, Jesse Hassenger of PopMatters described "Bobby Goes Nuts" as one of "the show’s finest episodes."^[11] Hassenger also observed that, "by season six, Peggy’s scales have tipped towards buffoonery; she essentially plays the bumbling, dim husband role. This role reversal is potentially clever, especially when Peggy’s decency, like Hank’s, is allowed to shine through."^[11] Screen Rant later ranked "Bobby Goes Nuts" first on their list of the show's top 25 episodes in 2023.^[12]

In a retrospective 2009 article, Jaime Weinman of Canadian magazine Maclean's had a more critical view of the season, writing that "the show continues to have some of the story arcs and emotional development (including having Bobby break up with his girlfriend) but the wackiness gets seriously out of hand: one episode combines a secret brainwashing cult and a car full of birds (emus, to be precise) in the same story."^[3] It has been mentioned that co-creator Mike Judge wasn't pleased with the overall direction of King of the Hill in the early 2000s, and that some involved with the show disliked the episodes "Returning Japanese", "Tankin' It to the Streets" and "Yankee Hankee" (from Season 5), due to their outlandish plots and the changes they made to the show's continuity.^[13] The Season 11 episode "Lucky's Wedding Suit", which was originally intended to be the series final, had an ending scene in the alley which explained that the episodes "Yankee Hankee" and "Tankin' It to the Streets" were just dreams Bill had after eating at a Hungarian restaurant. When the show got uncancelled by Fox, this scene was removed.