Charles Xavier was a British soldier in World War 2, fighting against German soldiers. At some point after the war, he was committed to a mental hospital. There he met Gabrielle, a Romani survivor of the Holocaust. He helped to bring her out of her catatonic state, and used his powers to coerce the hospital management into releasing both himself and Gabrielle. They were married soon after, and had a child.
Battle With the Shadow King
After David's birth, Charles received mysterious messages from another telepath, calling out to him. Despite Gabrielle's pleas not to go, he followed those messages to Morocco, where he was greeted by Amahl Farouk.
He psychically battled Amahl Farouk on the Astral Plane and defeated him. To protect his son from any possible threats that would arise in the future, David's father handed him over as an infant to Mr. Haller and Mrs. Haller. However, Farouk's lingering consciousness found David. Farouk rooted himself within the boy's mind, intending to take full possession of David's body and use his powers to exact revenge on the man who defeated him. 
After David Haller traveled back in time, Charles was warned of the threat Farouk posed and readied to go into battle against Farouk. However, before he could do so, the future version of Farouk proposed a truce to him, and he accepted. Together, the two of them convinced David and the past Farouk to make peace and accept the changed timeline.
Powers and abilities
- Telepathy: Charles is a very powerful telepath enabling him to read and manipulate the minds of others. He was able to enter the mind of Gabrielle Haller when they were both in a mental hospital, helping her to communicate and recover from her catatonic state. He was also able to scan the minds of Amahl Farouk's pet monkey and mute children who populated his palace to see that trapped within them were the minds of Morocco's former king and his subjects. During his time in the war, he was able to force an enemy soldier into committing suicide.
- Astral Manipulation: When Charles first met Amahl Farouk, he was introduced to the Astral Plane and was almost immediately able to create anything he could imagine. From a lush forest to an image of Gabrielle holding baby David. His power was so great that when Charles battled Farouk on the Astral Plane, he defeated him and drove him out of his body.
- Gabrielle Haller - wife
- David Haller - son
- Amahl Farouk - enemy
- Mr. Haller - raised his son
- Mrs. Haller - raised his son
- In the comics, Professor Charles Xavier is the father of David Haller.
- As of Season 3, Charles Xavier has been confirmed as David's father.
- "Chapter 7" (caricature)