Harmon Jurley was leader of Paradise Falls around 2250, and was a psychotic cannibal. Any slaves he couldn't sell, he ate. He was preceded by Penelope Chase, whose last act was enslaving the once-hidden settlement of Rockopolis.
He was the leader of Paradise Falls until Eulogy Jones killed him and took power.
Harmon Jurley is mentioned in Fallout 3, but does not actually appear.