As a boy, Pelops was slain by his own father Tantalus and offered to the gods in a banquet. Learning of his father's atrocity, they resurrected Pelops, and Poseidon took him to Olympus as his lover and apprentice in chariot racing. Drawing upon this apprenticeship and divine favour, the hero later beat king Oenomaus of Pisa, a polis very close to Olympia, in a chariot race so as to win his daughter's hand in marriage. To commemorate this victory, thank the gods, and honour the memory of Oenomaus, who had died during the race, Pelops established the Games.
The Pelopeion is a cenotaph (an empty tomb) traditionally considered a dedication to Pelops by Heracles, his fourth descendant. The Panhellenic and chthonic connotations of the myth are reinforced by the large, prehistoric stone tumulus at a depth of 2.5 metres under the monument. The tumulus is the most ancient building within the Altis, dating back to the Early Helladic Era (2500 BC), and its top could still be seen in the Classical Era. In the context of the hero cult, a black ram was sacrificed each year, always at night, before another sacrifice was made to Zeus at first daylight.