Since its earliest days, Captain America has been a fixture of the Marvel Universe, but Steve Rogers hasn't always been the hero behind Captain America's shield. But no matter what happens, the Star-Spangled Avenger always returns to the identity he created and defined.

At key points in Steve's life, he passed the title of Captain America on to three individuals: John Walker, Bucky Barnes and Sam Wilson. However, Steve didn't really go away while they were being Captain America, so what did he do with all of his free time?

RELATED: Captain America: Bucky Isn’t Steve Rogers’ Most Tragic Partner - It’s Nomad

Captain America US Agent

After briefly giving up his identity to operate as Nomad in the 1970s, Steve gave up the Captain America identity was when he was having issues with the obvious corruption he could see within the United States government, and his decision to renounce the title was prompted when he was ordered to work alongside that same government in 1987's Captain America #332, by Mark Gruenwald and Tom Morgan.. Unable to comply with this, but also recognizing that technically, the government owned the Captain America alias, Rogers gave up identity. Choosing to be his own agent of justice, Steve left that part of his life behind while the government found a replacement in John Walker, who did his best to emulate Steve.

But just because he left the Captain America identity behind does not mean that Steve was idle. He was still a hero in his heart and so he took up a new name, the Captain. During this time, Steve used an adamantium shield and even formed a new line up the Avengers after his usual team disbanded. But his time as the Captain would not last for long. When the Red Skull was revealed manipulating the Commission, Steve and John Walker resolved their differences to stop him. After which, John gave up the Captain America identity, the many deeds he did while filling in for Steve weighing on his soul, and that tension remained as Walker became U.S. Agent.

Captain America: Reborn

The second time Steve gave up the mantle of Captain America was less of a choice and more because he had no say in the matter, because he had seemingly been killed in 2007's Captain America #25, by Ed Brubaker and Steve Epting. Per Steve's wishes, Bucky Barnes became the new Captain America in the shadow of Civil War, letting go of his then title as the Winter Soldier. Even though Steve was technically dead though, his adventures would not end.

His body was physically killed, but his spirit was traversing through time, reliving key points of his life. Fortunately, his friends and allies managed to pull him from his timestream adventures, restoring him to his body. But Steve did not want to confuse the world by using the Captain America title again. And besides, he felt that Bucky had more than earned the title in his absence. So he let his former sidekick continue being Captain America and operated merely as Steve Rogers. After Bucky was seemingly killed in the Fear Itself crossover. a grief-stricken Steve once again became Captain America and led the Avengers on a quest for justice against Bucky's killers.

RELATED: Winter Soldier: Why Bucky Became Captain America - And Why He Stopped

Old Man Steve Rogers Captain America by Mike Deodato

At this point, it has become obvious that the only way Steve would ever give up being Captain America is if something happens that would either conflict with his morals or outright prevent him from being physically capable of performing his duties. Fortunately for Steve, what prevented him from being Captain America most recently was not quite as serious as death, but it was quite close to it in a literal sense. A battle with the Iron Nail neutralized the Super Solider Serum in Steve, resulting in him aging to his actual age of over 90 years old. Unable to be Captain America, Steve passed the title on to his good friend, Sam Wilson, in 2014's Captain America #25, by Rick Remender and Carlos Pacheco.

After the Marvel Universe was restructured, Steve became head of Civilian Oversight for S.H.I.E.L.D. He later learned that the spy organization had created a secret super-prison. The inmates had been reprogrammed to believe they were harmless civilians, but when they regained their memories they staged a breakout. Steve was nearly beaten to death by Crossbones (ironically the same man who killed him the first time), but was saved by the intervention of Kobik, a living Cosmic Cube, who restored him to his previous physical state and age. This opened up its own can of worms, but for the time being, Steve Rogers had once again returned as Captain America.

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