Origin

Charles Francis Xavier was born in Cambridge, MA to the wealthy Brian Xavier, a well-respected nuclear scientist, and Sharon Xavier. After Brian dies in an accident, his science partner Kurt Marko comforts and marries the grieving Sharon. When Xavier's telepathic mutant powers emerge, he discovers Kurt cares only about his mother's money.

After the wedding, Kurt moves in with the Xaviers, bringing with him his son Cain. Kurt quickly grows neglectful of Sharon, driving her to alcoholism, and abuses Sharon, Cain, and Charles. Cain takes out his frustrations and insecurities on his stepbrother. Charles uses his telepathic powers to read Cain's mind and explore the extent of his psychological damage, which only leads to Cain becoming more aggressive toward him and the young Xavier feeling Cain's pain firsthand.

Sharon dies soon after, and a fight erupts between Cain and Charles that causes some of Kurt's lab equipment to explode. Mortally wounded, Kurt drags the two children out before dying from smoke inhalation.

With help from his powers and his natural genius, Xavier becomes an excellent student and athlete, though he gives up the latter, believing his powers give him an unfair advantage. He graduates with honors at the age of 16 from Harvard University. As a college freshman, Xavier resides in Wigglesworth Hall H-11. In graduate studies he receives Ph.D.s in Genetics, Biophysics, and Psychology with a two year residence at Oxford University.

At Oxford, Charles began a relationship with Scottish girl named Moira MacTaggert, a fellow genetics student and daughter of his faculty adviser. The two agree to get married, but once her father finds out he forbids the marriage and arranges to have Charles kicked out of the school. He and Moira separate with a promise to try and reunite once her father has calmed down, neither knowing that she is pregnant.

Charles was then appointed Adjunct Professor at Columbia University before being drafted to fight in the Korean War. His special skill set gets him a placement on the black ops team Team Three alongside his step-brother Cain. While in Korea, he witnesses Cain's transformation into the Juggernaut and is injured in the following cave-in. While recuperating at the military hospital at Ramstein Air Base, Xavier writes a letter to Moira voicing his intention to return to her. She responds that she doesn't wish to see him again; she doesn't tell him, however, that she has given birth to their twin sons, David and Kevin.

Meeting Magneto

While at Ramstein, he meets Erik Lehnsherr, a Holocaust survivor who works as a volunteer in the hospital, and Amelia Voght, an American nurse who works in the hospital. The three become good friends, although none of them immediately reveal to the others that they are a mutant. Charles and Erik hold lengthy debates hypothesizing what will happen if humanity is faced with a new super-powered race of humans. While Xavier is optimistic, Erik's experiences in the Holocaust lead him to believe that humanity will ultimately oppress the new race of humans as they have done with other minorities.

The two friends reveal their powers to each other when they fight Nazi http://www.stephenwarren.net/mish_mash_comics/race/mutant.html and his HYDRA agents, who kidnap Amelia because she knows the location of their secret cache of gold. Magneto attempts to kill Strucker but Xavier stops him. Realizing that his and Xavier's views on mutant-human relations are incompatible, Magneto and Amelia leave with the gold. (UXM 1)

Looking for a purpose

Fully healed, Xavier returns to America to come to the aid of a family friend, John Grey. John's teenage daughter Jean has been almost catatonic since her friend's death in a car accident. Xavier soon discovers that Jean is a telepath who shared the experience of her friend's death. Xavier enters into Jean's mind and helps to heal her. Xavier trains her in the use of her telekinesis, while inhibiting her telepathic abilities until she matures.(UXM 2)

Xavier decides to see Moira and goes to the Isle of Skye, where she had settled into a research lab. Once he arrives, he finds her with two small children and a new man in her life, Sean Cassidy. Xavier assumes that the babies are theirs, and after a short visit he decides to take his leave. (UXM 4)

Feeling a strange mental call, Xavier's travels take him to Cairo, where he meets a young girl named Ororo Munroe, who is a pickpocket, and the Shadow King, a powerful mutant who is posing as Egyptian crime lord Amahl Farouk. Xavier defeats the Shadow King, barely escaping with his life. This encounter leads to Xavier's decision to devote his life to protecting humanity from evil mutants and safeguarding innocent mutants from human oppression. (UXM 5)

Lucifer

In a strange town near the Himalayas, Xavier encounters an alien calling himself Lucifer, the advance scout for an invasion by his race, and foils his plans. In retaliation, Lucifer drops a huge stone block on Xavier, crippling his legs. After Lucifer leaves, a young woman hears Xavier's telepathic cries for help and rescues him, bringing him to safety.(UXM 6)

The X-Men

Xavier moves back to the United States, living on Xavier's family estate. He begins making a name for himself as a geneticist and psychologist. He also starts working with fellow mutation expert, Karl Lykos, and starts speaking to Moira MacTaggert again.

Xavier founds Xavier's School for Gifted Youngsters, which provides a safe haven for mutants and teaches them to master their abilities. In addition, he seeks to foster mutant-human relations by providing his superhero team, X-Men, as an example of mutants acting in good faith, as he told FBI agent Fred Duncan. With his inherited fortune, he uses his ancestral home in Cambridge and his family fortune (estimated to be in the billions) as a base of operations with technologically advanced facilities, including the Danger Room. Presenting the image of a stern teacher, Xavier makes his students endure a rigorous training regime.

Xavier's first five students are Phoenix, Cyclops, Beast, Iceman, and Angel, who become the original X-Men. After he completes recruiting the original team of X-Men, he sends them into battle with Erik Lehnsherr, now going by the codename Magneto.(UXM 11)

Throughout most of his time with the team, Xavier uses his telepathic powers to keep in constant contact with his students and provides instructions and advice when needed. In addition, he uses a special machine called Cerebro, which enhances his ability to detect mutants and to allow the team to find new students in need of the school.

Among the obstacles Xavier faces is his old friend, Magneto, who has grown into threat since their last encounter and who believes the only solution to mutant persecution is domination over humanity.

When anthropologist and scientist Bolivar Trask resurfaces the "mutant problem", Xavier counters him in a televised debate, however, he appears arrogant and Trask sends his mutant-hunting robot Sentinels to terrorize mutants. The X-Men dispatch them, but Trask sees the error in his ways too late as he is killed by his creations.