Siege is an American comic book, published by Marvel Comics from January to May 2010. It deals with the climax of the "Dark Reign" storyline, which saw Norman Osborn become the United States primary defense officer, leading H.A.M.M.E.R. as well as employing his own evil Avengers. The story depicts Loki manipulating Osborn into leading an all-out assault on Asgard, at the time located within the United States. Captain America and his own Avengers lead a rebellion against Osborn. The events in Siege led to Marvel Comics introducing the subsequent storyline "Heroic Age".