Leonidas I (/liːˈɒn.ᵻ.dəs/ lee-on-i-dəs or /liː.əˈnaɪ.dəs/; Doric: Λεωνίδας [leɔːnídas], Leōnidas; Ionic Greek: Λεωνίδης, Leōnidēs; died 480 BC)[1] was a Greek warrior king of the Greek city-state of Sparta. He led the Spartan forces during the Second Persian War, and is remembered for his death at the Battle of Thermopylae. Leonidas was the third son of Anaxandridas II of Sparta,[2] and thus belonged to the Agiad dynasty, who claimed descent from the hero Heracles.