“Siege” is an American comic book storyline, published by Marvel Comics from January 2010 to May 2010. It deals with the aftermath of the “Dark Reign” company-wide storyline, which led to a shift of power in the Marvel Universe toward Norman Osborn, a former supervillain who, through deception and media manipulation, has become the United States’ security czar. The story also depicts the Asgardian trickster deity Loki, manipulating Osborn into leading an all-out assault to overthrow Asgard. The events in “Siege” lead to the subsequent company-wide storyline, “Heroic Age”.
Norman Osborn calls a meeting of the supervillain Cabal, consisting of Doctor Doom, the Hood, Taskmaster, and the Norse god Loki, to discuss Asgard, the home of the Norse gods, now located floating above Broxton, Oklahoma, and the last holdout in Osborn’s consolidation of power. A rift develops between Doom and Osborn, creating mayhem that appears to dissolve the group. Later, under his guise of respectability, Osborn attempts in vain to secure from the President of the United States permission to invade Asgard under the claim it poses a national security threat. On Loki’s advice, Osborn engineers a tragedy in which the hapless Norse god Volstagg, manipulated into battling the supervillain team the U-Foes, inadvertently causes an explosion that kills everyone in a crowded Soldier Field football stadium in Chicago, Illinois. This gives Osborn the pretext to lay siege on Asgard with military troops as well as with the Dark Avengers — his team of supervillains posing as superheroes — and with loyalists planted amid the various “50-State Initiative” teams of heroes.