Who Were the Ancient Kings of Sparta?

The ancient Greek city of Sparta was ruled by two kings, one from each of the two founding families, Agaidai and Eurypontidae. Spartan kings inherited their roles, a job filled by the leader of each family. Although not much is known about the kings — note how few of the kings listed below even have regnal dates — ancient historians have pieced together general information about how the government worked.

Sparta was a constitutional monarchy, made up of the kings, advised by and (supposedly) controlled by a college of ephors; a council of elders called the Gerousia; and an assembly, known as the Apella or Ecclesia. There were five ephors who were elected annually and swore fealty to Sparta rather than the kings. They were there to call up the army and receive foreign envoys. The Gerousia was a council made up of men who were over the age of 60; they made decisions in criminal cases. The Ecclesia was made up of every Spartan male full citizen who had attained his 30th birthday; it was led by the ephors and they supposedly made decisions on when to go to war and who would be the commander in chief. 

Having two kings share power was fairly common in several Bronze Age Indo-European societies; they shared power but had different roles. Like Mycenaean kings in Greece, the Spartans had a political leader (the Eurypontidae kings) and a war leader (the Agaidai kings). Priests were people outside of the regnal pair and neither of the kings was considered sacred — although they could enable contact with the gods, they were never interpreters. They were involved in certain religious or cultic activities, members of the priesthood of Zeus Lacedaemon (a cult group based honoring the mythical king of Laconia) and Zeus Ouranos (Uranus, the primal sky god). 

The Spartan kings weren't believed to be supernaturally strong or sacred, either. Their role in Spartan life was shouldering certain magisterial and juridical responsibilities. Although this made them relatively weak kings and there was always input from the other pieces of the government on most of the decisions they made, most of the kings were fierce and acted independently most of the time. Remarkable examples of this include the famed first Leonidas (ruled 490–480 BCE for the house of Agaidai), who traced his ancestry to Hercules and was featured in the movie "300".

• Chronology of Monarchical Rule (from the now-defunct Herodotus website)
• Adams, John P. “The kings of Sparta.” California State University, Northridge.  
• Lyle, Emily B. "Dumezil's Three Functions and Indo-European Cosmic Structure." History of Religions 22.1 (1982): 25-44. Print.
• Miller, Dean A. "The Spartan Kingship: Some Extended Notes on Complex Duality." Arethusa 31.1 (1998): 1-17. Print.
• Parke, H. W. "The Deposing of Spartan Kings." The Classical Quarterly 39.3/4 (1945): 106-12. Print.
• Thomas, C. G. "On the Role of the Spartan Kings." Historia: Zeitschrift für Alte Geschichte 23.3 (1974): 257-70. Print.