Stewart Gilligan "Stewie" Griffin is a fictional character from the animated television series Family Guy. He is voiced by the series creator Seth MacFarlane and first appeared on television, along with the rest of the Griffin family, in the episode "Death Has a Shadow" on January 31, 1999. Stewie was created and designed by MacFarlane himself, who was asked to pitch a pilot to the Fox Broadcasting Company, based on The Life of Larry and Larry & Steve, two shorts made by MacFarlane featuring a middle-aged man named Larry and an intellectual dog, Steve.

Family Guy is an American animated sitcom created by Seth MacFarlane for the Fox Broadcasting Company. The series premiered on January 31, 1999, following Super Bowl XXXIII, with the rest of the first season airing from April 11, 1999. The show centers around the Griffins, a dysfunctional family consisting of parents Peter and Lois, their children, Meg, Chris, and Stewie, and their anthropomorphic pet dog, Brian. Set in the fictional city of Quahog, Rhode Island, the show exhibits much of its humor in the form of metafictional cutaway gags that often lampoon American culture.