Agamemnon was the king of Mycenae. His father was Atreus and his mother, Aerope, the daughter of King Minos. His Brothers were Menelaus and Anaxives.
Because Thyestes killed his brother Atreus, the boys of Atreus, Agamemnon and Menelaus, fled to Sparta. There they married the daughters of King Tyndareus, Agamemnon wedded Clytemnestra and Menelaos the Beautiful Helen. Homer says Agamemnon acquired three daughters and a son, namely Chrysostomi, Laodice, Afianassa and Orestes. Other writers after Homer, instead of his last two daughters, mention Iphigenia and Electra.
Agamemnon managed to drive his uncle Thyestes from Mycenae and reign himself while Menelaus became King of Sparta. Later, when Paris stole the beautiful Helen from Sparta, the Greeks, led by Agamemnon, campaigned against Troy. The troops assembled in Aulis, Viotia. There, during a hunt, Agamemnon accidentally killed a deer, dedicated to the goddess Artemis. The goddess was angry and ordered no wind to blow. So the fleet could not start from the port, as the ships were sailing. Agamemnon then asked for help from oracle Calhas, who advised him to sacrifice his daughter Iphigenia. When "the sacrifice" took place, then only the Trojan campaign was possible.
During the siege of Troy, Agamemnon had a slave, Cressida, daughter of Chryssis, who was the priest of Apollo. Achilles had a slave, Briseida. But Agamemnon was forced to give Cressida back to her father, because Apollo had sent a bad illness (plague) to the camp of the Greeks. To replace her, he grabbed Briseida from Achilles. This was the reason for the two leaders to argue and to “split” the greek camp in half. Eventually they were reconciled.
When Troy finally fell, Agamemnon returned to Mycenae, bringing with him as a slave, Kassandra, the daughter of King Priam. There he found death from the hand of Clytemnestra and his cousin Aegisthus. Later, Orestes' son, with the help of Electra, avenged his death.