Asgard is a fictional realm and its capital city appearing in American comic books published by Marvel Comics. Created by Stan Lee, Larry Lieber and Jack Kirby, the realm first appeared in Journey into Mystery #85. Based on the realm of the same name from Germanic mythology, Asgard is home to the Asgardians and other beings adapted from Norse mythology. It features prominently in stories that follow the Marvel Comics superhero Thor.

Journey into Mystery is an American comic book series initially published by Atlas Comics, then by its successor, Marvel Comics. Initially a horror comics anthology, it changed to giant-monster and science fiction stories in the late 1950s. Beginning with issue #83, it ran the superhero feature "The Mighty Thor", created by writers Stan Lee and Larry Lieber and artist Jack Kirby, and inspired by the mythological Norse thunder god. The series, which was renamed for its superhero star with issue #126, has been revived three times: in the 1970s as a horror anthology, and in the 1990s and 2010s with characters from Marvel's Thor mythos. The title was also used in 2019 for a limited series as part of the "War of the Realms" storyline.