Bucky Barnes is known by a variety of names throughout his MCU run, but is rarely ever referred to by his actual first name — a decision that may ultimately reflect the journey The Winter Soldier has been through in the franchise.
Initially introduced as Captain America's closest friend, James Buchanan Barnes — known better by his nickname of Bucky — fast became a fan-favorite character after his reappearance as (and subsequent redemption from) the HYDRA controlled assassin known as The Winter
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