Winter soldier

Bucky is loyal, brave, honest to a fault, headstrong, resilient, and has a strong sense of justice and honor; during the 1940s he was charming and a ladies man, in present times he tends to be more distant and self-contained.

As the Winter Soldier, Bucky was an elusive, dangerous, and amnesiac assassin. He was ruthless, brutal, and under the complete control of HYDRA. After Steve Rogers reminded him of his past, Bucky broke from his programming and saved his friend and former target from drowning. After meeting him in his childhood, Bucky became Rogers' best friend. After the Pearl Harbor attack, Bucky joined the U.S. Army and attained the title of Sgt. Barnes.

The day before shipping out to England, Bucky saved his friend Steve from being beat up by a bully by punching him in the jaw and kicking him in the backside as he ran. Bucky and Steve then went to the Modern Marvels Pavilion on a double date Bucky had arranged, but Steve was more interested in attempting to enlist for the fifth time. Despite Bucky's protests, Steve still went through with it, but they parted on good terms before he did. Bucky and his regiment, the 107th, then shipped to England the next day.

A year later, Bucky and his regiment consisting of 200 men went up against a Nazi science division named HYDRA lead by Johann Schmidt at the orders of the SSR but 150 of the men were either killed or captured while 50 barely escaped. Bucky and the future Howling Commandos were among those captured. Bucky was taken to a prison camp in Austria where he was forced to work to build components for a super plane called the Valkyrie, but the enforced labour eventually became too much when he contracted pneumonia, and despite the efforts of his fellow prisoners to keep the HYDRA officers off his back, he was taken to an isolation ward for experimentation. But a little less than month later, Steve (who had become Captain America) infiltrated the base, freed the prisoners, and located Bucky strapped down to an examination table, suffering from whatever it was they had been doing to him. Steve freed Bucky and the two friends made their escape from the factory that was now self destructing. During the escape, Bucky and Steve encountered Schmidt and Zola but were able to evade them and flee the facility before it blew and then walked all the way back to the SSR base in Italy located more than 30 miles away.

After Steve's impressive job saving the prisoners, he was officially promoted to Captain and allowed to put together a special team. Bucky was of course completely on board with joining and following "that little guy from Brooklyn who was too dumb not to run away from a fight." Over the course of several months, Captain America and his team, now known as the Howling Commandos, went on special missions taking down HYDRA facilities and forces. On one of these missions, Bucky, Captain America, and Gabe Jones zip-lined onto the top of a HYDRA train carrying one of HYDRA's top scientists, Arnim Zola. They ran into trouble inside the train and a gun fight broke out, Steve temporarily went down, and Bucky took up his shield and saved him from enemy fire. But Bucky didn't have the upper body strength to hold on to the shield when hit with Hydra's powerful advanced weapons and the blast pushed him out of the blown open side of the train. Steve was unable to save him, and he fell hundreds of feet into an icy ravine below.