From my understanding, his name was Erik Lensherr for all intents and purposes until around 2009, when Greg Pak wrote the miniseries X-Men: Magneto Testament, in which it was retconned in that his birth name was Max Eisenhardt. He's working as a volunteer in an Israeli hospital when he meets Charles Xavier. Actually the name is composed of two German words: "Leh(e)n" meaning "feud" and "Herr" meaning "master" in that instance. Seeing this, the Nazi collaborator and secret mutant Sebastian Shaw had Erik brought to him.

Peter was born in the mid 1950s to the powerful mutant Erik Lehnsherr and Ms. Maximoff. He is one of the X-Men's most dangerous foe. When first incarcerated with his family, Erik pulled apart a metal gate as he was separated from his parents. Erik Lehnsherr was a German mutant with the ability to manipulate metal. Seeing this, the Nazi collaborator and secret mutant Sebastian Shaw had Erik brought to him. When first incarcerated with his family, Erik pulled apart a metal gate as he was separated from his parents.

At the age of sixteen he goes on the hunt for the men who murdered his parents, and assists in odd-jobs to get by, such as factory work. Erik Lehnsherr was a German Mutant activist and supremacist, who eventually became the terrorist known as Magneto.Erik was a formidable opponent, even for Telepaths, as he possessed Shaw's Helmet, which allowed him to avoid having his mind manipulated.Erik's supremacist tendencies sprouted from his time in the Nazi Concentration Camps, where he was tortured by Sebastian Shaw.
The number tattooed on Magneto's arm at Auschwitz was 214782. But when World War II struck, the Jewish Erik was in trouble. Nina Gurzsky was the daughter of Erik Lehnsherr, and a mutant who influenced animal behavior. his most common alias is Erik Magnus Lehnsherr. Her name … Erik Lehnsherr had always been misunderstood. Wundagore. Magneto’s real name is Max Eisenhardt.
This attempted retcon was corrected a few years later when it was revealed that the name "Erik Lehnsherr" and the Sinte ethnicity were part of a cover identity, as mentioned above. Erik retaliates. As a boy, Erik was forced to live in a death camp during the Holocaust. In German 's' is a connective between two combined words sometimes. He was forced to help the Nazis kill people, something that Erik hated doing. Erik Lehnsherr was a German Mutant activist and supremacist, who eventually became the terrorist known as Magneto.Erik was a formidable opponent, even for Telepaths, as he possessed Shaw's Helmet, which allowed him to avoid having his mind manipulated.Erik's supremacist tendencies sprouted from his time in the Nazi Concentration Camps, where he was tortured by Sebastian Shaw. After fleeing the United States and settling in Poland, Erik Lehnsherr met a woman named Magda and the pair got married and conceived a girl who they named Nina. In the prequel to the X-Men film trilogy, the origins of how Erik Lehnsherr becomes Magneto are explained.