|First appearance||"Fantastic Four #10"|
Mar-Vell was a peasant on the streets of Hala. When he reached the age of seven he was taken and inducted into the military. Pretty quickly he became a General.
Mar-Vell was sent as a spy to Earth. He posed a man named Daniel, and he didn't know that the Kree kidnapped a man to build their weapons. He formed a relationship with his co-worker, Carol Danvers. He knew it was time, so he summoned the beacon, but Carol found it before him and she was imbued with Kree energy and she becomes Ms. Marvel.
Mar-Vell pretended he had been affected too and he turns into his true form. He goes by Captain Marvel, but when the Kree come he betrays the humans, breaking Carol's heart. When he sees the destruction the Kree are causing, he betrays them and kills the Supreme Intelligence. He is then left behind on Earth when the Kree evacuate.
Before he could be captured Mar-Vell went into hiding. He resurfaced later in a new form, claiming to be the new Captain Marvel.