The Man with the Peacock Tattoo is one of many clones of David Moreau, the Genegineer, created by him for experimentation. He grew up jeleous of Moreau's true sons, Phillip and Thomas. He was badly injured in a lab experiment, his face horrifically burned. He escaped the facility where he was raised.
He longed to kill his creator, but Moreau died, and so he instead devoted himself to beating Moreau's incomplete legacy, founding Xeno to harvest the power of mutant biology.