Sparta was an important Greekcity-state in the Peloponnesus. It was unusual among Greek city-states in that it maintained its kingship past the Archaic age. It was even more unusual in that it had two kings simultaneously, coming from two separate lines. According to tradition, the two lines, the Agiads and Eurypontids, were respectively descended from the twins Eurysthenes and Procles, the descendants of Heracles who supposedly conquered Sparta two generations after the Trojan War. The Agiad line was regarded as being superior to the Eurypontid line. [1] Although there are lists of the earlier purported Kings of Sparta, there is little evidence for the existence of any kings before the middle of the 6th century BC or so.
Leonidas I c.490 - 480 BC. (Leonidas, a half-brother of Cleomenes, took the throne instead of his heir, Gorgo; instead Leonidas was married to Gorgo who, as Queen of Sparta, had a very powerful, influental role)
Eucleidas227 - 221 BC (Eucleidas was actually an Agiad - his brother Cleomenes III deposed his Eurypontid colleague and installed his brother as co-king).