Doctor Evil
Dr. Evil is the father of Scott Evil and arch-enemy of Austin Powers and, ironically, his brother. He was born Dougie Powers and separated from both his brother and their father, Nigel Powers, when he was just a baby. Dougie was found by some Belgians and raised to be evil, and took the name of Evil by the time he attended spy acadamy in England, where he was roommates with Austin. He held a grudge against Austin for most of the rest of his life after he became that year's International Man of Mystery.
After attending Evil Medical School and becoming Doctor Evil, he established an evil empire (which he called, aptly, the Evil Empire) whose single goal was taking over the world. His many underlings included the Germanic Frau Farbissina, who would become Scott's mother, the eyepatch-wearing Number 2, who he first met at the spy acadamy, and the seemingly unkillable Mustafa.
His evil plans included cryogenically freezing himself in 1967, then returning in 1997 and plotting to detonate a nuclear warhead within the Earth's core, inventing a time machine and going back to 1969 with his clone, Mini-Me, to steal Austin's mojo, and finally teaming up with Goldmember (recruited from 1975) in a scheme to melt the polar ice caps and flood the planet.
It was during this latter plan that he learned from Nigel Powers that he was, in fact, Dougie Powers and therefore Austin's brother. Much to the consternation of Scott, Dr. Evil/Dougie turned good and helped Austin and Foxxy Cleopatra stop Goldmember.