The Marvel Cinematic Universe's expansion to Disney+ with connected series like WandaVision and The Falcon And The Winter Soldier has continued to develop the growing world of heroes and villains with new characters like John Walker, who took over for Steve Rogers as the new Captain America.

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Comic fans who know that character are preparing for his eventual debut as his own costumed hero known as the U.S. Agent. But there are quite a few other facts about the new MCU character that could have an effect on his cinematic future. We'll be exploring those further today with a look at John Walker/U.S. Agent's comic history.

10 Gained His Powers To Compete In The Unlimited Class Wrestling Association

Captain America walking through the Unlimited Class Wrestling Federation gym

The MCU's John Walker shares his military history with his comic counterpart, though he failed to find the same success and recognition as the MCU version. This led Walker to undergo a dangerous process from the Power Broker to gain superpowers.

With the process successful, Walker first tried to find his fame as a fighter in the superpowered Unlimited Class Wrestling Association, which characters like Ben Grimm/Thing, Justice, and D-Man have fought in over the years. though he quickly found a new calling.

9 He Began His Costumed Career As Super-Patriot

Super-Patriot vs Captain America

Walker's empowerment by the Power Broker was successful and his strength was dramatically increased, though his agent convinced Walker that he had a future outside of the wrestling ring as a costumed hero.

Inspired by his brother's military service and his own love of country, John Walker became the conservative-leaning Super-Patriot and began a campaign of discrediting Steve Rogers/Captain America. He also worked alongside the Bold Urban Commandoes (BUCs) for a time, which included his future partner Lemar Hoskins/Battlestar after he was chosen to replace Captain America.

8 Violently Murdered The Watchdogs Who Killed His Parents

His parents were killed and he turned on his former partners

When Walker began serving as Captain America, his name was leaked to the public by his former partners in the BUCs who had become Left-Winger and Right-Winger after Walker abandoned the group with Battlestar.

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An extremist group known as the Watchdogs then used that leaked information to find and murder Walker's parents, which sent him over the edge. Walker, as Captain America, killed the Watchdogs who murdered his parents and then beat and nearly killed Left-Winger and Right-Winger in an explosion before they later took their own lives.

7 He Faked His Death As Captain America To Start Over As U.S. Agent

The Assassination of John Walker/Captain America

While Walker's time as Captain America was filled with controversy as he became the villains he was fighting against, he was prepared to hand the costume and title back to Steve Rogers after the two heroes found common ground.

However, given his previous actions that tainted his name with the public, it was decided he would be able to continue his work as the U.S. Agent in secret. So the Commission on Superhuman Activities faked the public assassination of Walker so he could begin his new life as the government's own costumed hero.

6 Has Worn Multiple Costumes Over The Years

U.S. Agent wore a few different costumes

While he first appeared in the Super-Patriot costume before upgrading to the actual Captain America suit, John Walker has continued to change his uniform in dramatic new ways over the years. His first U.S. Agent costume was the uniform formerly worn by Steve Rogers when he went by The Captain, and that suit saw a few modernized upgrades over the years.

He also was given a high-tech upgrade by Tony Stark that completely changed his look and weaponry before the U.S. government reoutfitted him in a new helmeted version of his black costume. His most recent new comic look falls more in line with his suit from The Falcon And The Winter Soldier.

5 Worked With The West Coast Avengers And Force Works

West Coast Avengers and Force Works

Walker has worked with quite a few teams over the years as U.S. Agent, which began with his government-appointed position on the West Coast Avengers. He created a few issues on the team with his confrontational attitude.

However, he proved himself time and time again and earned his place on the West Coast Avengers, which also earned him spots on teams like Force Works. U.S. Agent would continue to work with other connected teams like the Mighty Avengers as well as government-created teams like the Jury over the years, proving his worth as a team player.

4 He Was Once Prison Warden For The Entire Planet

US AGENT was a prison warden of Earth

U.S. Agent's work with the CSA led to his appointment as leader of S.T.A.R.S./Superhuman Tactical Activities Response Squad, which first appeared during the Maximum Security event that saw Earth transformed into a galactic prison planet by the Kree Supreme Intelligence.

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Given his leadership role and commitment to justice at any cost, he was chosen to operate as the warden of Earth's new prison, though he turned on his new masters and coordinated the heroes of Earth in their fight to end the alien occupation of their planet.

3 Briefly Worked With Canada's Omega Flight And The New Invaders

Omega Flight and New Invaders

After Marvel's Civil War introduced the Superhuman Registration Act and divided the heroic community, U.S. Agent sided with Iron Man's Pro-Registration side where he was tasked with rounding up superheroes and villains that violated the new act. He was placed with Canada's Omega Flight team following the death of Alpha Flight, which didn't sit well with the patriotic hero.

So when the call came for him to take Captain America's place on the international New Invaders, he jumped at his short-lived second chance as the Sentinel of Liberty. Everyone else still referred to him as U.S. Agent until the team separated after the death of Jim Hammond/Human Torch.

2 Became The Director Of The Government's Thunderbolts Program

John Walker as the Thunderbolts director.

While Baron Zemo first created the Thunderbolts as a disguise for his Masters of Evil in a plan for world domination, the former villains decided to follow their new heroic paths and reform away from Zemo. The success of the heroic members of the Thunderbolts inspired the government to officially introduce the Thunderbolts program, which gave supervillains a chance to reform.

The program went through a number of iterations until it settled on The Raft and appointed the retired John Walker (who had been seriously injured) as the new Warden and director of Thunderbolts program alongside Luke Cage.

1 Was Mentally Coerced Into Leading The Dark Avengers

U.S. Agent and the Dark Avengers

It was during Walker's time with the Thunderbolts that he found himself transported to an alternate reality alongside a few members of the team, which provided the means to restore his body so he could resume his place as U.S. Agent.

Unfortunately, a brilliant geneticist with artificial powers named Toxie Doxie was able to take control of Walker's mind as they fought to return back to their home dimension. He was mentally coerced into becoming the leader of a new Dark Avengers once they returned, though he was eventually able to free himself and leave the team.

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