What 1979 film was the first to feature the Muppets as main characters?

The 1979 film that first featured the Muppets as main characters was The Muppet Movie.

Directed by James Frawley and produced by Jim Henson, The Muppet Movie was the Muppets’ first theatrical feature film. Its musical road-comedy story follows Kermit the Frog as he travels cross-country toward Hollywood, meeting characters such as Fozzie Bear, Miss Piggy, Gonzo, and the members of the Electric Mayhem along the way.

The movie functions as a fictional origin story for the troupe: the characters share a goal of finding success in show business and gradually come together. It also established the franchise’s blend of fourth-wall jokes, celebrity cameos, songs, and backstage-style comedy on a feature-film scale.

The film premiered in the United Kingdom on May 31, 1979, and opened in the United States on June 22. Its song “Rainbow Connection” received an Academy Award nomination, helping make the movie a lasting part of Muppet history.