The first and last line of the series was "Yep".

The voice of Boomhauer is based on a message left on Mike Judge's telephone answering machine by an irate viewer of Beavis and Butt-Head (1993).

Boomhauer's job is not stated for most of the series. Near the end of the final episode, a shot shows a badge in his wallet, identifying him as a Texas Ranger.

The third longest running primetime animated series.

In addition to providing the voice of Luanne, Brittany Murphy voiced the young Joseph Gribble. When Joseph hit puberty, Breckin Meyer took over the role.

Before Cotton Hill's shins were blown off, he stood 6' 4". After that, he was 5' even.

Hank, Bobby, Peggy, Luanne, Bill, Dale, and Boomhauer were animated into an episode of The Simpsons (1989). At one point, Homer makes a reference to the Springfield football team playing the Arlen football team, then, the shot goes to the Hill family, where Hank says "We came two thousand miles for this?" The rest of the characters do not speak. In an episode of King of the Hill, Bobby also has a Bart Simpson doll on his bookshelf.

Joseph's middle name is John, in honor of his biological father John Redcorn.

This show was passed over for renewal in September 2005, which would have made season ten its final season. The order for new episodes was only made after production had ended on the show. The renewal for the eleventh season was due to the high ratings of season ten.

Kahn's license plate reads "KINGKAHN".

In nearly every episode of the show, Hank, Dale, Bill, and Boomhauer stand in the alley and drink beer. Creator Mike Judge has described the four of them as like "the Greek chorus of the show".

Hank's full name is Henry Rutherford Hill.

In the episode where Bobby is afflicted with gout, he eats at a deli that has portraits of famous comedians on the wall. One portrait is Johnny Hardwick, the voice of Dale.

A live-action Monsignor Martinez pilot was filmed, but never aired.

From the second season on, many episodes end with a line of dialogue from that episode being repeated.

Dale Gribble's looks are based on actor Robert Patrick.

The last name of the character Bill Dauterive is an homage to the series writer Jim Dauterive.

How and when the show's last episodes would air became a point of uncertainty after FOX officially cancelled it early in 2009. The network originally planned to show unaired season thirteen episodes at some point in the early 2009 - 2010 season. It was later speculated that ABC would pick up the show for a fourteenth season, but the idea was shot down by ABC's President. FOX later said it would not air any of the season thirteen episodes, and fans believed they would premiere on either the cable Cartoon Network or a season thirteen DVD. In the end, two new episodes comprising a series finale aired on FOX on September 13, 2009.

Joseph Gribble is the name of a character in the Marx Brothers movie Room Service (1938).

The Luann Platter is a type of combination plate available at Luby's Cafeteria, a popular restaurant in Texas (In the show, it's referred to as "Luly's"). It has a meat, a roll, and a side for a low price.

Luanne's middle name is Leeanne.

The town of Arlen is in Heimlich County, Texas. Both are fictional.

In season three, episode twenty-two, "Death and Taxes", on the list of prison guards is the name Alex de Large, a reference to the central character in A Clockwork Orange (1971)

Boomhaur's first name is Jeff.

The voice of Lucky is Tom Petty.

The Hills' ZIP code is 78104. The code is real, and is located in the town Beeville, Texas.

The character of Stuart Dooley is based on Butt-head.

Mike Judge and Greg Daniels pitched the show to FOX network executives, as an animated pencil sketch, featuring all the main characters with Hank doing the pitch.

Bill's full name, with military rank, is Sergeant Barber William Fontaine Delateur Dauterive. He stands 5' 8-3/4", and was born in Louisiana, or "Loser-ana" as Dale described it.

The character of Hank Hill is based on a character in Beavis and Butt-Head (1993), by the name of Tom Anderson, who acted and talked exactly like Hank. Also, Hank's catchphrase of "That boy ain't right", was from an episode of "Beavis...", when they're at Burger World, and Tom Anderson comments on Beavis, by saying, "That boy ain't right in the head."

Stephen Root was uncredited during the first few seasons. This was because he was also on NewsRadio (1995), and his contract prevented him from being credited on another network's show. After the show was cancelled in 1999, he was able to be credited for this show.

Season three, episode twenty-two, "Death and Taxes" has a death row inmate named "Wesley Martin Archer". Bobby comments that it's a good name for a killer. This episode was directed by Wesley Archer.

Throughout the series, on the rare occasion that Bobby is seen playing Little League, he wears #3. This is an homage to Babe Ruth, another husky baseball player. This connection is confirmed in "King of the Hill: Bad News Bill (2009)", when the coach refers to him as "Great Bobino", a nod to Ruth's nickname of "Great Bambino".

Cotton Hill's voice is based on Ross Perot's.

Stephen Root (voice of Bill) also worked with Mike Judge in Office Space (1999), playing Milton.

Whenever someone refers to John Redcorn, they use his full name. Not once in the series is he referred to by his first name only (he is referred to as Mr. Redcorn however).

This show features the last television appearance of John Ritter, who reprised his role as the voice of Eugene Grandy, the junior high school teacher during season eight. The episode was "King of the Hill: Stressed for Success (2004)," which was broadcast on May 2, 2004.

Each time a character is seen reading a book, it is "A Dinner of Onions". This book is first seen in the episode where Peggy and Hank go to a book club, and that was the assigned book.

When Cotton flees to Las Vegas, all of the hotel and casino names are fictional, but are parodies of real ones. For instance, the Golddust is a parody of the Stardust.

Bobby has a Bart Simpson doll on the top shelf of his bookcase.

Co-creators Mike Judge and Greg Daniels in talks with FOX about a possible revival, with Seth Macfarlane rumored to produce, as of August 8, 2017.

There is no beer based on King of the Hill's "Alamo Beer". The Real Ale beer is actually called "Remember Alamo Golden Ale", but only in San Antonio, Texas. Everywhere else, it is called "Real Ale Firemans #4". Actually, as anyone who has ever been to Texas realizes, "Alamo Beer" is a parody of "Lone Star Beer", which has long semi-facetiously advertised itself as "The National Beer of Texas". This presentation is done along the same lines as "Luly's" for "Luby's", or "The Renaissance Faire" for "The Texas Renaissance Festival" and other satirical, yet apparent-to-locals, ways around potential copyright infringement. "Whataburger", on the other hand, is presented as-is, as are the "Dallas Cowboys".

Whenever John Redcorn talks about his Native American heritage, a mysterious wind comes up and blows his long hair.

Following the season two cliffhanger ending, rumors begin spreading through various FOX commercials and promotional spots that the Hills would be moving to Hollywood. TV Guide ads and the like even touted Propane Boom (the season two finale) as the "last episode in Texas!" This was all later, of course, revealed to be a hoax, meaning that show show itself (not the characters on the show) was moving to another night on the network, a move that nearly killed the series. Fortunately, this was later rectified, and the show eventually regained the coveted Sunday night prime time slot for the remainder of its run.

This show would go on to become Mike Judge's longest-running animated series, running for thirteen years, with Beavis and Butt-Head (1993) running for four years, then being revived in 2011, and The Goode Family (2009) lasting only one year.

Breckin Meyer and Brittany Murphy appeared in Clueless (1995), before voice acting on this show. Both of them voiced the same character, albeit at different stages of that character's life. Brittany Murphy voiced Joseph Gribble before he went through puberty, and Breckin Meyer voiced Joseph Gribble after he went through puberty. Murphy also voiced Hank's niece, Luanne Platter.

Stephen Root, who voiced Bill, originally auditioned for the part of Dale.

Mike Judge came up with the idea for this show in 1995.

The school which Bobby Hill attends, Tom Landry Middle School (named after the Dallas Cowboys football coach), really does exist. It is located in Irving, Texas, in the subdivision of Valley Ranch, just a few blocks down MacArthur Boulevard from the Dallas Cowboys' office and training facility (most of the streets in the neighborhood are also named after Dallas Cowboy greats). This is not a middle school, but an elementary school in Valley Ranch.

The Hills' dog is named Lady Bird after Lady Bird Johnson.

According to the season one DVD commentary, Bobby Hill's full name is Robert Jeffrey Hill.

Cotton's middle name is Lyndal.

In the episode about voting for the Presidential candidate, Dale suggested to Hank that he was born in Ecuador. In real life, co-Creator Mike Judge (voice of Hank Hill) was born in Ecuador.

Bill Dauterive's ex-wife's name is a reference to Edgar Allen Poe's "The Raven".

Dale's middle name is Alvin.

Dale's "Dale's Dead Bug" van is a 1990 Dodge Ram minivan.

In season nine, episode ten, "Arlen City Bomber", Lucky (Tom Petty) tells Bobby that he would help him "run down that dream" after Bobby lements that he would like to taste a corn chip right off of the line. This is a reference to Tom Petty and the Heartbreakers song, "Running Down a Dream".

Producer John Altschuler created the character of Lucky Kleinschmidt. He described the him to Series Creator Mike Judge as a guy who "ought to look like Tom Petty without the success". This led producers to pursue Petty to provide the voice for the character, and to their surprise, he enthusiastically agreed.

Hank is 6' 2" and weighs 220 pounds. His weight is correctly and accurately stated in "Dale to the Chief".

In season two, episode seven, "The Man Who Shot Cane Skretteburg", the three main members of Green Day (Billie Joe Armstrong, Mike Dirnt, and Tre Cool) voiced the garage band teens.

Peggy's favorite song is Gloria Estefan's "Can't Stay Away From You".

Hank's mother, Tillie, has the middle name "Mae".

Hank is seen as owning two pick-up trucks in the series. At the start of the series, he drives a 1997 Ford Ranger. Later in the series, when he is forced to replace his truck, due to it being hit by a train, he upgrades to a Ford F-250. (The model year is unknown.)

Dale's birthday is July 12.

The melody played by Mr. Strickland's car horn is "Yellow Rose of Texas".

Bass Pro Shops, the company that appears on Hank's fishing hat, is an actual chain of stores.

This show was originally planned to premiere at the start of the 1996-1997 season in September of 1996, but it premiered mid-season for unknown reasons.

"That's Amore", the upscale Italian restaurant seen in the series, takes its name from a Dean Martin song.

In the episode with the diving pig at the fair, the pig's most difficult dive is called the "Johnny Cash", and it must dive through a flaming ring. This is a direct reference to Johnny Cash's song "Ring of Fire".

"That boy's not right" are also lyrics to the Richard Marx song "Hazard".

Dale wears a hat with Mack (the big truck company) on it.

Kathy Najimy said that she did not know how she developed the voice of Peggy.

The license plate on Dale's truck is LXD-352.

In the pilot episode, Seinfeld (1989) is mentioned.

The license plate on Hank's pick-up truck is JD3-170.

Peggy's maiden name is Platter.

Bobby enjoys eating fruit pies.