Winter Soldier

James Buchanan "Bucky" Barnes (Winter Soldier) is a World War II veteran, former sergeant of the 107th Infantry Regiment, best friend of Steve Rogers since childhood, and a founding member of the New Avengers. Barnes enlisted in the Army after the attack on Pearl Harbor and was assigned to the 107th in 1943. His unit was captured by Hydra, where Arnim Zola injected him with the Super Soldier Serum. Barnes was rescued by Rogers, who had become Captain America. Barnes and Rogers then formed the Howling Commandos to combat the forces of Red Skull. However, during the attempt to finally capture Zola in the Austrian Alps, Barnes fell into an ambush and plummeted hundreds of meters. As no body was recovered, Barnes was presumed dead and honored as a hero who died serving his country.

Unbeknownst to his team, Barnes' enhanced abilities allowed him to survive the fall, albeit with the loss of his left arm. Once he was found by the Soviet Armed Forces and Hydra, Barnes was brainwashed and armed with a new cybernetic arm to become their operative, known as Winter Soldier. Over the next seventy years, he killed anyone who posed any kind of threat to Hydra or the Soviet Union, including John F. Kennedy, as well as Howard Stark and his wife, Maria. Between missions, Winter Soldier would be put back into cryogenic stasis to ensure his longevity. In 2014, Alexander Pierce ordered Winter Soldier to kill Nick Fury, to ensure that all of Pierce's plans with Project Insight could move forward. However, Winter Soldier was challenged by Steve Rogers, which led him to begin to remember his previous life.

Following the Battle of the Triskelion, Barnes, now free, abandoned Hydra to remember his past and put an end to his long and violent history.