Ultron was created by the original Ant-Man, Doctor Henry “Hank” Pym. Dr. Pym also founded the Avengers with his wife, Janet van Dyne (AKA the Wasp), whom Ultron would come to consider a mother.
Inspired by his studies of Professor Gregson Gilbert’s synthetic being Dragon Man, Pym began experimenting with artificial intelligence. After building a structurally crude robot (a torso on tank treads with spindly arms), Pym endowed it with consciousness using a copy of his own brain patterns as the basis for the robot’s programming. However, the robot inherited not only Pym’s great intellect, but his inherent mental instability—only without a human conscience.