Oenomaus - King of Pisa in Elis

Oenomaus was the son of Ares and the Pleiad Sterope. He was the king of Pisa, in Elis [see map of the Peloponnese section Bb], and the father of Hippodamia. Oenomaus offered his daughter to whoever could beat him in a chariot race. Whether he feared an oracle about his death at the hand of Hippodamia's suitor or he was in love with his own daughter, his motive is unclear. Using treachery, Oenomaus managed to win all the races until Pelops set his mind to marrying his daughter. Pelops or Hippodamia induced the charioteer of Oenomaus, Hermes' son Myrtilus, to loosen the lynchpins in Oenomaus' quadriga. As a result the king died, but before he died, he cursed Myrtilus which led indirectly to more troubles for the House of Atreus.
Commemorating the death of Oenomaus, Olympic games were established in honor of Zeus, either by Pelops or Hercules.

The Ancient Olympics - Starting Point for Information on the Olympics