John Hansen (voice actor)

South Park is an American adult animated sitcom created by Trey Parker and Matt Stone who also do the majority of the voices. Both Parker and Stone do most of the male characters on the show along with April Stewart and Mona Marshall, who do the female characters on the show. Guest stars have lend their voices to the show including Jay Leno, George Clooney, Robert Smith and the comedy duo Cheech & Chong voiced characters representing their likenesses for the season four (2000) episode "Cherokee Hair Tampons", which was the duo's first collaborative effort in 20 years.

Characters in the show, according to Parker and Stone, are inspired by people they met when they were kids. Stan Marsh is made based on Parker himself while Kyle Broflovski is based on Stone himself. Eric Cartman is partially named after and based on Matt Karpman, a high school classmate of Parker who remains a friend of both Parker and Stone. Cartman is also inspired by All in the Family patriarch Archie Bunker, of whom Parker and Stone are fans. They state that creating Cartman as a "little eight-year-old fat kid" made it easier for the two to portray a Bunker-like character after the introduction of political correctness to late-20th century television.Kenny McCormick was based on the creator's observation that most groups of childhood friends in small middle-class towns always included "the one poor kid" and decided to portray Kenny in this light.Butters Stotch is loosely based on South Park co-producer Eric Stough.

Some of the original voice actors left the show. Mary Kay Bergman voiced the majority of the female characters until her suicide on November 11, 1999. Mona Marshall and Eliza Schneider succeeded Bergman, with Schneider leaving the show after its seventh season (2003). She was replaced by April Stewart, who, along with Marshall, continues to voice most of the female characters. Issac Hayes, who voiced the character Chef, left the show after Parker and Stone's depiction of his religion Scientology in the episode Trapped in the Closet.

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Wikipedia