Twelve Olympians
The Greek cult of the Twelve Olympians can be traced to 6th century BCE Athens and has no apparent precedent in the Mycenaean period. The altar to the Twelve Olympians at Athens is usually dated to the archonship of the younger Pesistratos, in 522–521 BCE. By the 5th century BCE, there are well-attested cults of the Twelve Olympians in Olympia and at the Hieron on the Bosphorus.