While Magneto has yet to appear in the Marvel Cinematic Universe, but one unexpected plot development revealed that he has a far more personal connection to a movie villain than anyone knew existed.
Magneto, born Max Eisenhardt but also known as Erik Lensherr, has one of the most famously tragic backstories in superhero comics. As a child he survived the Holocaust, losing his family and suffering physical and psychological trauma. His experiences during World War II established the foundation for his later obsession with mutant liberation. Having seen genocidal horrors firsthand, Magneto swore he would not let that happen to his newfound mutant brethren and began a decades-long crusade that pitted him against Charles Xavier and the X-Men. Magneto has tempered his vision recently, going from fighting for mutant supremacy to cautious coexistence as a leader of Krakoa. However, Erik still has unresolved trauma from his youth - and an issue of Uncanny Avengers revealed he came close to suffering even more at the hands of the Red Skull.
In Rick Remender and John Cassady's Uncanny Avengers #2, the Nazi leader Johann Schmidt, also known as the Red Skull, has been resurrected in modern times and is using telepathy stolen from Charles Xavier to sow discord between mutants and humans. As part of his plan, he kidnaps the Scarlet Witch and tries to persuade her to join his anti-mutant crusade. During the speech, he tells her (and the readers) something never-before-stated on panel: the Red Skull was aware of Magneto's powers during Erik's imprisonment in Auschwitz. Mutants were largely unknown at the time, and powers such as Erik's were exceedingly rare, so the Red Skull had plans to "focus the entirety of [his] attentions on him." Fortunately for Magneto, Captain America's efforts kept his longtime nemesis from being able to dedicate himself to studying this new discovery, and the pair only met as adults decades later.
Magneto has long reviled Nazis for the Holocaust and has come to blows with the Red Skull on several occasions. But this admission by the Skull shows that he was involved in Magneto's life since childhood, and Max very nearly became a lab rat for Schmidt. Fans have seen something similar to this relationship in 2011's X-Men: First Class, which portrayed longstanding X-Men villain Sebastian Shaw as a wartime Nazi officer who tortured the mutant antihero in an attempt to harness his powers. Magneto never forgave him or moved on from the trauma, hunting him down decades later and killing him in the film's climax.
While Magneto and Red Skull's connection isn't that strong, the news that the Nazi villain knew of the young mutant - and considered experimenting on him or having him killed - is a smart way of making Magneto's hatred even more personal. Magneto has attacked Red Skull in the past for his participation in the Nazi regime, but this detail takes their animosity to the next level, as well as laying the ground for fresh revelations about how Schmidt may have altered the life of the Master of Magnetism. Great comic nemeses have been built on far less, and now that Magneto is working with the X-Men, he's in need of new enemies who speak to his own story and experiences.
Following the revelation of their early connection, the door is open for Magneto to seek out the Red Skull and find more answers about his origins. If Magneto decides to seek revenge against his first nemesis, the Red Skull would be advised to flee even farther than his movie counterpart's cosmic exile on Vormir.