Eurysthenes

Together they received the land of Lacedaemon after Cresphontes, Temenus and Aristodemus defeated Tisamenus, the last Achaean king of the Peloponnesus.

[2] The title of archēgetēs, "founding magistrate," was explicitly denied to Eurysthenes and Procles by the later Spartan government on the grounds that they were not founders of a state, but were maintained in their offices by parties of foreigners.

[3] The story of the double kingship of Sparta begins with the invasion of the Peloponnesus by the Dorians, and the Aetolian allies, under three Heraclid commanders, Temenus, Cresphontes and Aristodemus, the three sons of Aristomachus.

A second asserts that he died before taking possession and that the Dorians brought his infant twin sons to Sparta as kings under a regent.

The oracle at Delphi resolved the problem by suggesting that they both be made kings, which is the origin of the dual monarchy.

[2] The untimely death of Aristodemus with other events has served as some basis for dating the reigns of the first ten kings of Sparta in the line known by state definition as the Agiad.

[8] According to Isaac Newton, also a classical scholar, the ten kings reigned an average of 38 years each, which can be used as an estimator of the dates.