Thyestes killed Atreus. While Thyestes ruled Mycenae, the sons of Atreus, Agamemnon and Menelaus, were exiled to Sparta. There, King Tyndareus accepted them as the royalty that they were. Shortly after, he helped the brothers return to Mycenae to overthrow Thyestes, forcing him to live in Cytheria, where he died. As a token of good will and allegiance, King Tyndareus offered his daughters to Agamemnon and Menelaus as wives, Clytemnestra and Helen respectively. When Agamemnon left Mycenae for the Trojan War, Aegisthus seduced Agamemnon's wife, Clytemnestra, and the couple plotted to kill her husband upon his return. They succeeded, killing Agamemnon
History of Sparta northern borders. The final showdown saw Philip fighting Athens and Thebes at Chaeronea. Sparta was pinned down at home by Macedonian allies such as Messene and Argos and took no part. After the Battle of Chaeronea, Philip II of Macedon entered the Peloponnese. Sparta alone refused to join Philip's "Corinthian League" but Philip engineered the transfer of certain border districts to the neighbouring states of Argos, Arcadia and Messenia. During Alexander's campaigns in the east, the Spartan king, Agis III sent a force to Crete in 333 BC with the aim of securing the island for Sparta. Agis next took