Thanks to Marvel’s Captain America film series, the world now knows “Bucky” Barnes as well as Steve Rogers himself. In The First Avenger, he was introduced as Captain America’s closest friend, and a fellow soldier during World War II. What followed gave audiences a condensed version of the decades-long story: his presumed death helping Cap fight the Red Skull, his transformation into a memory-wiped assassin, and his mission to kill Captain America as the mysterious Winter Soldier.

Meeting his old friend restored Bucky’s memories, and he helped Cap beat his former HYDRA masters before disappearing again. All of which is based on the original Captain America comics, especially Ed Brubaker and Steve Epting’s 2005 story The Winter Soldier. But what turned out to be a small twist in the movie for fans (especially viewers who already knew Bucky survived, or had that spoiled for them) was an absolutely enormous one in the comics. The MCU films may have hit the broad points of Steve and Bucky’s friendship, but they departed from the original comics in key ways.

How Bucky Barnes Joined Captain America

For starters, the original Bucky wasn’t a beefcake like Sebastian Stan (not at first, any way), but one of the wave of kid sidekicks that invaded comics on the success of Batman’s iconic sidekick, Robin. This original version of James Buchanan Barnes was the teenage mascot of Steve Rogers’s platoon. After Bucky caught Steve changing clothes and learned he was really Captain America, Cap decided to let him join his adventures. The comics have tweaked this over the years, making Bucky a highly trained and carefully selected sidekick, but the pair ended up fighting together until the series ended in 1949.

There was a brief, Cold War-themed revival in 1955, but Captain America didn’t really make his comeback stick until Stan Lee and Jack Kirby brought him onto The Avengers. Possibly realizing what an anachronism a rah-rah patriotic hero was in the era of protests against American racism and wars, they reinvented him as a literal man out of time. Near the end of the war, he had been frozen in suspended animation after falling off an experimental “robot plane” flying over the Atlantic. As for his young sidekick Bucky? Well…

The Death of Bucky Barnes

Stan Lee famously hated kid sidekicks, so he took the opportunity to write Bucky out by revealing the plane’s creator, Baron Zemo, had rigged it to explode. Captain America survived, but Bucky died in the blast. This turned out to be a brilliant decision, since it meant Captain America was no longer the one-dimensional do-gooder he’d been during the war. Now he had to deal with the kind of guilt and inner turmoil that had defined Lee’s other heroes, like Spider-Man and the Hulk.

Where the movie version of Bucky was hardly mentioned between his death and return, Bucky’s death would continue to define Captain America in the comics for most of his existence. Fans liked to say that he, Batman’s parents, and Spider-Man’s Uncle Ben were the only characters you could always count on to stay dead. Just a few years before Bucky returned, he even appeared in Alan Moore and Gene Ha’s Top Ten as a panhandler with a sign that said, “Really dead, please help!” It remained that way until Ed Brubaker’s very first page of his very first issue on Captain America, when he set the stage to reveal… Bucky wasn’t really dead at all.

Bucky Becomes The Winter Soldier

The comic book version wasn’t revived by the fictional HYDRA, but by the very real supervillains of the KGB. Even though the Soviet Union had fallen, one agent, Aleksander Lukin, still had access to some of their most dangerous weapons, which he was hoping to sell to the Red Skull. Looking at a metallic arm that has since become familiar to millions of moviegoers, the Skull gasps, “This can’t be what I think it is?” But the issue reveals that arm is exactly what he thinks, as the Winter Soldier arrives to shoot him on the final page.

Over the next year Captain America (and readers) would begin to piece together this mystery man’s identity, with Brubaker and Epting dropping several hints before finally revealing the secret. In one flashback, the context of Bucky’s early appearances was completely changed to bring him more in line with the ruthless Winter Soldier. It turned out his origin was only a cover story. In reality, he wasn’t an innocent child, but a cold-blooded assassin who could sneak behind enemy lines to do the dirty work Captain America could never be caught doing. But that reveal was nothing next to the one which followed. It turned out Bucky had also survived the explosion of the robot plane, falling into suspended animation himself–so that when a Soviet expedition went searching for Captain America’s body years later, they found him instead.

Replacing his lost arm with a mechanical one, the Soviets erased Bucky’s memory and turned him into the USSR’s Winter Soldier. Cryogenically frozen between missions, in the past sixty years he had only aged ten. As in the movie, Cap began to suspect the truth after seeing his unmasked face. But unlike the movie, seeing Cap wasn’t enough to restore Bucky’s memories. Instead it took all the power of the Cosmic Cube, but not the disguised Infinity Stone of the MCU. The original Cosmic Cube, with the ability to do nearly anything the user can imagine. Channeling The Lion King Captain America tells Bucky to “Remember who you are.”

Bucky destroys the Cube and disappears in the aftermath, but over the next year, readers would see him reconciling his old life as a hero with his new career as an assassin. Much like the movie version, Bucky’s return eventually ceased to be a shocking change to the canon, eventually being accepted as a modern part of it. And when Steve was apparently killed following Marvel’s Civil War, Bucky even became Captain America himself. That may not have been his fate in the movies, but with Bucky and Falcon getting their own TV series, James Barnes is going to keep redefining the Winter Soldier role for a long, long time.

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