Here Ludger Pistor and Wilfried Hochholdinger portray Nazi soldiers which Michael Fassbender‘s character confronts in the bar scene. Pistor and Hochholdinger also played Nazis in Inglourious Basterds (2009), and Fassbender played an Allied soldier.

To prepare for his role as Charles Xavier, James McAvoy shaved his head… and learned that the filmmakers wanted Xavier to have a full head of hair in the prequel.  Throughout the first month of filming McAvoy had to wear hair extensions.

Bryan Cranston turned down the role of Sebastian Shaw to be in Drive (2011).

Amber Heard was rumored to play Mystique before Jennifer Lawrence was cast.

The film was originally to be a prequel about Magneto. Screenwriter Sheldon Turner wrote a treatment which he described as “X-Men (2000) meets The Pianist (2002)”: the story focused on Magneto’s early years as a prisoner of war in a Nazi concentration camp, until liberation by a squad of Allied Forces led by Charles Xavier. They later meet after the war and become friends, and later become rivals. The studio decided to change the film’s direction to the early years of the X-Men, but incorporated aspects of Turner’s script into the film.

The uniforms the X-Men wear are colored blue and yellow, in homage to the original blue/yellow suits the X-Men wore in the comics from 1963.

In addition to his comic book persona, the character of Sebastian Shaw (Kevin Bacon) takes on qualities of Nazi scientist Josef Mengele. Mengle is noted for his eugenic experimentation and torture often with children, to whom he would offer candy to gain their trust.