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 to take advantage of the ensuing chaos, dispatched Philopoemen to Sparta with a large army. Once there, he compelled the Spartans to join the Achaean League ending their independence. Sparta played no active part in the Achaean War in 146 BC when the Achaean League was defeated by the Roman general Lucius Mummius. Subsequently, Sparta become a free city in the Roman sense, some of the institutions of Lycurgus were restored and the city became a tourist attraction for the Roman elite who came to observe exotic Spartan customs. The former Perioecic communities were not restored to Sparta and some