Katar Hol was the most decorated police officer on the distant world of Thanagar, until he was accidentally transported to Earth. Using advanced Thanagarian technology, he disguisesn himself as a human archaeologist named "Carter Hall." He has a partcular interest in the ancient Egyptian pharoah Khufu, claiming to be a descendet of him. This claim is in fact true, as Khufu was actually a Thanagarian, Katar's ancestor in fact, who crashed on Earth millenia ago. As a police officer, Katar has a strong sense of justice which, led to him deciding to fight crime on Earth. He joined the Justice League some time after the Joining invasion. He helped fight off an invasion of Earth by his own people, which he was intended to be a part of, leading the people of Earth to distrust Hawkman.