Sadyattes, son of Ardys II, was King of Lydia from 624 BC to 610 BC. He was succeeded by his son Alyattes II. The Greeks nicknamed him Candaules, 'the dog-strangler', after a name of the Lydian god Hermes. Herodotus wrote (in Inquiries) that he fought with Cyaxares, the descendant of Deioces, and with the Medes, drove out the Cimmerians from Asia, took Smyrna, which had been founded by colonists from Colophon, and invaded Clazomenae and Miletus. After ruling for twelve years he was assassinated by his former friend Gyges, who succeeded him on the throne of Lydia.
Gyges soon became a favourite of Sadyattes and was despatched by him to fetch Tudo, the daughter of Arnossus of Mysia, whom the Lydian king wished to make his queen.
Forewarned that the king intended to punish him with death, Gyges assassinated Sadyattes in the night and seized the throne with the help of Arselis of Mylasa, the captain of the Carian bodyguard, whom he had won over to his cause.
Civil war ensued, which was finally ended by an appeal to the oracle of Delphi and the confirmation of the right of Gyges to the crown by the Deiphian god.