Cyaxares was the third king of the Medes. Cyaxares ascended to the throne in 625 BCE, after his father Phraortes lost his life in a battle against the Assyrians.

The Medes were an ancient Iranian people who spoke the Median language and who inhabited an area known as Media between western and northern Iran. Around the 11th century BC, they occupied the mountainous region of northwestern Iran and the northeastern and eastern region of Mesopotamia in the vicinity of Ecbatana. Their consolidation in Iran is believed to have occurred during the 8th century BC. In the 7th century BC, all of western Iran and some other territories were under Median rule, but their precise geographic extent remains unknown.