The Coda originated from the planet Khera, where three female Kherubium warriors came to Earth. When they arrived on said planet is unknown, but they've been around at least since the Trojan War and are considered to be the Amazon warriors of Greek mythology. They began training human women only in the art of fighting, since it was a proud tradition of the Kherubium. Their first leader was Zealot, from the WildC.A.T.s. When the Coda member Andromache became their Majestrix, or leader, they became a cult of hired assassins, their skills on sale for the highest bidder.
As an important ritual for the initiation to become a full Coda member, they would have to drink some blood of a Kherubim alien, because it would grant them a very long life.
The Coda's base of operations lied on the top of Mount Themiscyra, in Greece.