There have been many heroes who have wielded the shield of Captain America. From Steve Rogers to Sam Wilson, there’s always been someone to step up and take over the mantle when the Marvel Universe needed it the most.

But Bucky Barnes’ time as the Sentinel of Liberty wasn’t the role’s most traditional tenure. And with his past as the Winter Soldier, it’s no surprise that he was a very different Captain America than any who had come before him.

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12 Captain America 600 Bucky Barnes The Falcon

The original partner of Captain America during World War II, Bucky Barnes was seemingly killed facing Baron Zemo in the same incident that left Steve Rogers in suspended animation. Thought dead for decades, Barnes returned as the assassin called Winter Soldier in the “Winter Soldier” storyline of 2004’s Captain America by Ed Brubaker, Steve Epting and Frank D’Armata.

Revealed to have been found and brainwashed by the KGB, Barnes worked as their Winter Soldier for decades and was kept in stasis between missions. As a part of Alexander Lukin’s scheme to get the Cosmic Cube, Bucky is put back on Steve’s radar when he assassinates the Red Skull. After he kills the hero called Nomad and firebombs Philadelphia, Buck’s memories are restored by Steve and the Cube. Barnes goes underground once again, working for Nick Fury to move against their enemies and seeking vengeance on his former masters and the Red Skull-possessed Lukin.

When Steve is murdered after the Civil War event by Mark Millar, Steve McNiven and Dexter Vines, Bucky plans to assassinate those he considers responsible for Rogers’ death: Red Skull and Tony Stark. Stealing the shield of Captain America in transit, Bucky reunites with his old lover, the Black Widow.

Bucky Barnes as Captain America

Barnes is later captured by Lukin, escapes with the help of Falcon and Sharon Carter, and ends up in S.H.I.E.L.D. custody where he tries to kill Stark. He relents when a regretful Iron Man shares a letter from Steve revealing their friend’s last wishes: to save Bucky and to find a successor. Agreeing to take up the mantle of his fallen friend, Bucky has Tony clear him of any remaining brainwashing, and Stark outfits him as the new Cap, with the agreement that he answers to nobody.

As Captain America, Bucky continued to combat the Skull’s schemes, took on Arnim Zola and A.I.M., and faced the mad Grand Director, a high-powered super-soldier who thought he was the real Steve Rogers. It wasn’t until he stopped the Skull’s daughter, Sin, from assassinating presidential candidates that he earned public approval as the new Captain America. Buck continued to serve, fighting the Skrulls during Secret Invasion, by Brian Michael Bendis, Leinil Yu and Mark Morales, before joining the New Avengers.

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When Steve returns in Captain America: Reborn by Ed Brubaker, Bryan Hitch and Butch Guice, Bucky planned to retire as Cap. But after seeing Bucky and Widow in action, Steve wouldn't let him, officially giving his successor his shield and his blessing. The two Captain Americas fight side by side during the events of Siege by Bendis, Olivier Coipel and Mark Morales, with Bucky temporarily returning the shield to Steve as he led the heroes into battle against Norman Osborn’s forces.

After Siege, Bucky joined the primary Avengers team, and once again fought the Grand Director. He infiltrated his Watchdogs and defeated him with the help of Falcon before Baron Zemo outed his past as Winter Soldier. Though found innocent in an American court, Barnes is extradited to Russia and imprisoned. He escaped with Black Widow after it’s revealed to be a scheme involving Russia’s Red Room. With his past brought to light, it is decided he’s too tainted to continue as Captain America.

Taking up the mantle one final time, Bucky is seemingly killed by a Skadi-possessed Sin during Fear Itself by Matt Fraction, Brubaker and Stuart Immonen. It is soon revealed that he faked his death, seeking redemption as the Winter Soldier once again to right the wrongs of the past, with only Nick Fury, Steve Rogers and his partner Black Widow knowing the truth.

While it may have been fraught with controversy, Bucky Barnes’ time as Captain America proved he could live up to the mantle and still be his own man, redeeming his legacy in the process. Should Steve Rogers once again need to lay down the shield, he’ll have no shortage of worthy successors—including the Winter Soldier.

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