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
Menelaus (son of Lagus) when Demetrius Poliorcetes arrived in Cyprus with a powerful fleet and army. Unable to contend with this formidable antagonist in the open field, Menelaus drew together all his forces, and shut himself up within the walls of Salamis, which he prepared to defend to the utmost. But having risked an action under the walls of the town, he was defeated with much loss; and Demetrius pressed the siege with his wonted vigour. Menelaus, however, succeeded in burning his battering engines; and by the most strenuous exertions, made good his defence until the arrival of Ptolemy himself, with a powerful fleet,