The History of Super-soldiers in MCU
“Dr. Erskine is dead… and his formula died with him! There can be no more like me! But I shall fight for all those who might have been!” (Steve Rogers in Tales of Suspense #63, March 1965)
In the classic Marvel Comics canon, Steve Rogers was the first and only super-soldier. 1941’s origin story of Captain America told us that Rogers received the super-soldier serum just before an undercover spy kills the scientist responsible for creating it. With the formula lost forever, the U.S. Army sent Rogers to fight on behalf of the army of super-soldiers that never existed.
However, as we know, the concept of uniqueness can be quite elastic in Marvel Comics (as much as the concept of death). Since then, different comic book creators have written storylines with other experiments and dozens of super-soldiers besides Captain America.
Now, the same happens in the Marvel Cinematic Universe (MCU). As this article is being written, we already have at least two dozen known super-soldiers in the movies and TV shows. Just the recent series The Falcon and the Winter Soldier introduced 10 new super-soldiers at once! And there’s probably even more to come.
Let’s take a look at the concept of Marvel’s super-soldiers, their chronology, and their evolution in the MCU.
The Red Skull
The genesis of Marvel Comics’ super-soldier serum began in Nazi Germany during World War II. Dr. Abraham Erskine was one of the scientists working on the so-called Projekt Nietzsche. At some point during World War 2 he decided to switch sides and help the Allies with his formula.
Part of this plot was used in the script for Captain America: The First Avenger. The film also introduces Red Skull as the first super-soldier of the MCU – albeit in an imperfect, evil version.
In his comic version, Johann Schmidt aka Red Skull is just a Nazi soldier who wears a skull-shaped mask. Over the years, the villain would have clones, robotic versions, and so on. But he was never a super-soldier in the first place.
In the MCU, Schmidt is the leader of the paramilitary terrorist organization HYDRA. He decides to inject himself with the first, unstable version of Abraham Erskine’s super-soldier serum in 1940. The formula increases his strength and intelligence. However, its horrible side effects deform Schmidt’s face forever, making it look like a red skull.
The Red Skull thus becomes one of the most terrifying villains in the MCU. He was also the first to locate the mysterious relic known as the Tesseract. As we all know, this thing would later cause a lot of chaos in the Marvel Cinematic Universe.
At the end of the first Captain America movie, Red Skull is sucked into a wormhole created by the Tesseract. He ends up becoming one of the immortal keepers guarding the Infinity Stones.
Captain America
Both the MCU and comic book chronology are similar when it comes to Captain America’s origin. In both, Dr. Erskine flees to the United States to perfect his formula and help the Allies instead of the Nazis.
During the events of the first Captain America film, Dr. Erksine heads Project Rebirth with fellow scientist Howard Stark, father of the future Iron Man Tony Stark.
In 1943, during New York’s Stark Expo, the scientist meets a young man named Steve Rogers. Steve wants to fight the Nazis in the war but is too skinny to enlist. Erksine decides to use Rogers as a volunteer for the new version of the super-soldier serum.
Rogers receives injections of the formula and is bombarded with Vita-Rays inside a chamber. The experiment works and gives him superhuman abilities. When Erksine is killed by a Nazi spy, he became Captain America and helps the U.S. Army as the only super-soldier on the good guys’ side. At least for a while.
The MCU chronology makes it clear that Rogers was Project Rebirth’s only test subject. In the comics, it was that way until the 1980s. More recently, some stories have changed the canon introducing other experiments before Steve.
Bucky Barnes aka The Winter Soldier
Is Bucky Barnes a super-soldier?
Yes, he is! Chronologically, the MCU’s third super-soldier is the childhood friend of Steve Rogers. Sergeant James Buchanan Barnes was serving on the front lines during World War II when he was captured with his unit in late 1943, just a few months after the creation of Captain America.
Captain America: The First Avenger shows the hero rescuing his pal in October 1943. He finds Bucky tied up to a stretcher as if he was being subjected to some kind of experiment.
Does bucky have super-soldier serum?
Sometime later, Captain America: The Winter Soldier confirms it. HYDRA’s scientist Arnim Zola experimented on Bucky to recreate Erskine’s super-soldier serum. The prisoner received a new version of the formula that gave him enhanced strength and stamina.
The formula saved Bucky’s life in early 1945 when he falls off a cliff and disappears (as shown in Captain America: The First Avenger). The whole scene is a recreation of the events narrated in Avengers #4 (March 1964). In the comics, however, Bucky “died” in a plane explosion during World War II.
Captain America: The Winter Soldier shows Bucky surviving the cliff fall and the loss of his left arm. He is rescued by Soviet troops and imprisoned in another POW camp. While Barnes was presumed dead, Dr. Zola continued experimenting with his new super-soldier. It was the start of the Winter Soldier Program.
Bucky’s severed arm was replaced with a cybernetic prosthesis and his memory was erased. The good guy then becomes a super-assassin, codename Winter Soldier. HYDRA keeps freezing and unfreezing him for the next 50 years.
Barnes was rescued again by Captain America in 2014. His original memories were reactivated and he became a good guy again. Or at least for now. He continues to deal with some issues from his past life, as we saw on The Falcon and the Winter Soldier.
In the Marvel Comics chronology, Bucky returned as the Winter Soldier in Captain America #11 (November 2005). But in that story arc, written by Ed Brubaker, he never received any super-soldier serum.
Isaiah Bradley
The fourth super-soldier of the MCU is Isaiah Bradley. The character was recently introduced in The Falcon and The Winter Soldier.
After the events of the first Captain America movie, the U.S. Army believes Cap is dead. They use Steve Rogers’ blood samples to try to replicate Erskine’s super-soldier serum during the 1950s (and the Cold War).
In The Falcon and The Winter Soldier, Bucky introduces Sam Wilson to a Korean War veteran named Isaiah Bradley. He was the sole survivor of these experiments. Bucky and Bradley originally met as enemies in 1951.
Isaiah explains that several Black soldiers were given samples of the new super-soldier formula. The only one who received superpowers was him. With all his friends dying during the experiments, Bradley rebelled and was sentenced to life imprisonment. He managed to escape 30 years later and lived in hiding since the 1980s.
Isaiah Bradley’s origin was based on the comic book miniseries Truth: Red, White & Black (2002). The story arc showed the US Army trying to replicate Project Rebirth during World War II. 300 African-American soldiers were used as guinea pigs and only a few men survived. They formed a covert black-ops team used on dangerous missions. At the end of the conflict, the only survivor was Bradley. Court-martialed in 1943, he was released in 1960 and forced to live in secrecy ever since.
Also in the comics, Isaiah’s grandson Elijah Bradley later became a super-soldier. He received superpowers thanks to his grandfather’s blood transfusion. Eli takes on the name Patriot and becomes one of the Young Avengers.
In the MCU, Elijah Bradley has already been introduced in The Falcon and The Winter Soldier. But there’s still no evidence that he also has superpowers.
The Soviet Super-Soldier Program
During the Cold War, the Soviet Union had its own super-soldier project according to the MCU. Bucky Barnes spent years at a Russian POW camp after World War II. His blood sample was likely collected and analyzed to replicate Erskine’s original serum.
The first (and for now only) volunteer on the Russian program was Alexei Shostakov. He became the Red Guardian, as depicted in the Black Widow film. The movie also explains that the Red Guardian was extremely popular as a communist hero during the Cold War days, with a uniform that mimicked Captain America but in red colors (he even wore his own shield!).
With the end of the Soviet Union in 1991, Alexei was sent as a spy to the United States. He lived undercover with a fake family made up of Black Widow Program super-killers (including young recruits Natasha Romanoff and Yelena Belova).
In the late 1990s, Alexei was betrayed by his former general and incarcerated for decades at Seventh Circle Prison in Russia. He was rescued by Natasha in the events depicted in Black Widow. The film features a funny aged and out-of-shape version of the former Russian super-soldier.
In the comics, Alexi Shostakov/Red Guardian was created by Roy Thomas and John Buscema. As shown in Avengers #43 (June 1967), he was a Soviet Union pilot trained by the KGB. But his comic book version never received the super-soldier serum. Ironically, Alexei was the first husband of Natasha Romanoff (his “daughter” in the movie).
The Failed Winter Soldier Program
During flashbacks in Captain America: Civil War, we see Bucky Barnes in 1991. Still working for HYDRA as The Winter Soldier, he’s sent to kill Howard Stark. At the time, Tony’s father had created an improved version of the super-soldier serum.
In the same year, HYDRA used the formula stolen from Stark to expand their Winter Soldier Program. Five volunteers received doses of the serum. They received super strength and powers like Captain America. But they also began to suffer from mental instability – a side effect of the new formula.
Difficult to control, these Winter Soldiers were kept in Cryostasis Chambers at HYDRA’s Siberian facility. They were finally located and exterminated by Baron Helmut Zemo during the Civil War.
To date, Bucky is the only successful result of both the replicated super-soldier serum and the Winter Soldier projects.
Bruce Banner’s Experiment
In the comics, The Incredible Hulk was not linked to Erskine’s super-soldier serum at all. His 1962 origin story, by Stan Lee and Jack Kirby, showed Dr. Bruce Banner working on the creation of a new Gamma Bomb. During one of the tests, he saves a boy from an explosion and ends up receiving a massive dose of Gamma-Rays. Because of this, Banner starts to mutate into a green giant called Hulk.
But the MCU preferred to connect Hulk’s origin with the super-soldier serum. In the film The Incredible Hulk, Dr. Banner is enlisted by the U.S. Army to work on recreating Project Rebirth shortly after 9/11.
The scientist replaces the Vita-Rays that created Captain America with the new Gamma-Rays. In 2005, he test the new serum on himself, thus turning into a green monster. Banner fled and some time later became one of the most powerful members of the Avengers.
But before that could happen, the Army pursued Banner in The Incredible Hulk movie. Emil Blonsky, a British special-ops commander, was recruited to receive the new super-soldier serum. At the end of the day, he was still defeated by Hulk’s superior powers.
Unable to face failure, Blonsky takes a transfusion of the Gamma-irradiated blood taken from Banner. The mix turns him into a monstrosity called Abomination. The villain was once again defeated at the end of The Incredible Hulk.
Since then, Banner’s replicated super-soldier serum has never been used again (at least for now). Blonsky reappeared in 2024 as one of the fighters in an illegal tournament in Macau, as shown in Shang-Chi and the Legend of the Ten Rings.
The Abomination also has a different origin in Marvel Comics. In Tales to Astonish #90 (April 1967), Emil Blonsky was portrayed as a communist spy. Trying to discover the secret of the Gamma-Rays, he ends up receiving an almost lethal amount of them and turning into another huge green monster.
The Flag Smashers
The main antagonists of The Falcon and The Winter Soldier are the Flag Smashers, an anti-nationalist group whose members had super-soldier powers. Led by Karli Morgenthau, they act Robin Hood-style trying to lessen social injustices in the MCU after Thanos and the Blip.
The Flag Smashers stole the super-soldier serum from a scientist called Wilfred Nagel. He was recruited first by HYDRA and then by the CIA to recreate Erskine’s super-soldier serum. Nagel used Isaiah Bradley’s blood and tissue samples in his experiments, conducted in Madripoor.
Karli and her friends stole and used eight vials of the formula. Later on, Baron Zemo kills Dr. Nagel and destroyed the recreated super-soldier serum, making the Flag Smashers the last of their kind. All the members of the group appear to have been eliminated at the end of the series. But some fans claim that at least one of them (Diego, the guy in the helicopter) may have escaped.
Although it was created for the TV show, the Flag Smashers had roots in the comics. Karl Morgenthau (whose name inspired the leader of the group) was originally an enemy of Captain America. Created by Mark Gruenwald and Paul Neary, he made his debut in Captain America #312 (December 1985). Karl was a terrorist without any super-soldier power who went by the nom de guerre... Flag-Smasher!
Dr. Wilfred Nagel also exists in the comics but comes from an earlier chronology. In the aforementioned Truth: Red, White & Black miniseries, he was the scientist responsible for experimenting with African-American soldiers during World War II.
John Walker
The Falcon and The Winter Soldier introduced several new super-soldiers and the last of them is John Walker – the tenth super-soldier of the series and, for now, the twenty-first of the Marvel Cinematic Universe.
When Sam Wilson decides to return Captain America’s shield, the decorated U.S. Army captain Walker is chosen to succeed Steve Rogers as the new Cap. Extremely fit and athletic, he uses the suit and shield masterfully. But Walker has no superpowers.
After being defeated by the Flag Smashers, John concludes that he will never measure up to Rogers without the super-soldier serum. Thus, he steals and uses one of Dr. Nagel’s vials. Unfortunately, the new Cap also uses his newfound powers to take revenge and kill one of his enemies. Walker ends up losing the Captain America stuff and also his Army rank.
At the end of the series, John Walker is recruited to act “independently” as the U.S. Agent. He receives a new, all-black version of the Captain America costume. It’s still a mystery how the character will be used in the future of the MCU.
Both John Walker and the U.S. Agent come from the comics. The character was created by Mark Gruenwald and Paul Neary and first appeared in Captain America #323 (November 1986). He was a nationalist anti-hero called the Super-Patriot. Walker later inherited the Captain America costume and name for some time when Rogers decided to retire. But the new Cap’s violent methods made Steve change his mind. Walker then became U.S. Agent. But the comic book version of the character never took any kind of super-soldier serum.
More to Come?
Urban legends and conspiracy theories allege that the great powers are trying to reproduce some kind of super-soldier serum in real life.
A recent BBC News article revealed that U.S. Intelligence has been investigating reports of secret experiments carried out in China. Hmmm... Captain China doesn’t sound so good, but maybe his shield could be even cooler!
Meanwhile, it’s hard to predict the future of super-soldiers in the MCU. But with The Falcon and the Winter Soldier practically exhausting the subject by creating nearly a dozen new characters, any new or old version of the infamous serum will likely be left on the side for a while.
Furthermore, the recent TV series Hawkeye has proven that Marvel Studios can create an entire and successful series without resorting to super-powered heroes and villains.
Either way, there are currently four functional super-soldiers left in the MCU: Bucky Barnes, Isaiah Bradley, the Red Guardian, and John Walker. Among the villains, the Red Skull and Emil Blonsky/Abomination are unlikely to appear again, but they bring the total of cinematic super-soldiers to six.
Some might be tempted to also add Captain Carter, the alternate version of Peggy Carter who received the super-soldier serum in place of Steve Rogers in a parallel universe, as we saw in one of the episodes of the TV series What If... From now on, if the MCU takes inspiration from the comic book chronology, there are several more or less known super-soldiers to feature at some point.
Only during World War II, we have the British hero Destroyer (later renamed Union Jack) and the villain Master Man, who took the Nazi version of the serum. It’s doubtful either of them will feature in an already packed MCU, and Peggy Carter was already introduced as a British super-soldier in one of the episodes of What If… But you can never say never.
From the 1970s onwards, super-soldiers were more common than mutants in Marvel’s magazines: among others, there’s the Nazi spy Warrior Woman, long-haired vigilante Jack Monroe aka Nomad, the X-Men villain Warhawk, Captain America’s nemesis Protocide, among several others.
The super-soldier serum continues to create new heroes and foes in comics to this day. Recently, female heroine Mockingbird was dying and had her life saved by receiving an injection of the serum (and its consequent superpowers). Will there be room for Mockingbird in the MCU? Perhaps in Phase 22...
But it’s good to keep an eye on Eli Bradley, Isaiah’s grandson, who may have inherited his powers by blood, and on John Walker, whose history as a tragic antihero could receive his own TV show soon.
The only certainty is that, as with Marvel Comics, we hardly ever hear the last word when it comes to super-soldiers. And Steve Rogers is definitely not the one and only, although he is certainly the most famous and successful of them all.
