In Greek mythology, Agamemnon was king of Mycenae (or Argos) and commander of the Achaean forces in the Trojan War. Son of Atreus and Aerope (or, in some traditions, of Pleisthenes), brother of Menelaus, and husband of Clytemnestra, he led the Greek expedition after Helen's abduction and quarreled with Achilles over the captive Briseis in Homer's Iliad. On his return he was murdered by Clytemnestra and her lover Aegisthus — central events of the Oresteia and the curse of the House of Atreus.
Adapted from Wikipedia, "Agamemnon" · CC BY-SA 4.0
I.Ancestry and early life
Agamemnon belonged to the House of Atreus, descended from Pelops son of Tantalus. Homer makes him and Menelaus sons of Atreus and Aerope; another tradition makes them sons of Atreus's son Pleisthenes, raised by Atreus after Pleisthenes died young. Their sister Anaxibia (or Astyoche) married Strophius.
Atreus's feud with Thyestes — adultery, the banquet of Thyestes' children, and Aegisthus's murder of Atreus — drove Agamemnon and Menelaus into exile. Sheltered by Tyndareus of Sparta, they married his daughters Clytemnestra and Helen; some plays have Agamemnon kill Clytemnestra's first husband Tantalus and their infant before the marriage. With Menelaus's help Agamemnon expelled Aegisthus and Thyestes, recovered Mycenae, and became the most powerful prince in Greece.
Sources disagree on his children with Clytemnestra. The Iliad names Chrysothemis, Laodike and Iphianassa; Aeschylus's Oresteia gives Orestes, Iphigenia and Electra; Sophocles adds Chrysothemis.
II.Commander at Troy
When Paris took Helen, Agamemnon invoked the Oath of Tyndareus and gathered the Greek fleet at Aulis. Artemis's anger — variously explained — stalled the ships until the prophet Calchas demanded the sacrifice of Agamemnon's daughter Iphigenia. Some versions carry out the sacrifice; others have Artemis substitute a deer and carry the girl to Tauris, or transform her into Hecate.
In the Iliad Agamemnon's seizure of Achilles' war-prize Briseis, after he is forced to return the captive Chryseis to end Apollo's plague, causes Achilles to withdraw from battle and nearly ruins the Achaeans. Agamemnon later offers rich amends; Achilles returns only after Patroclus's death. Homer portrays Agamemnon as the embodiment of kingly authority — summoning councils and leading in battle — but also as haughty; his aristeia in Book 11 ranks him among the foremost Achaean fighters after Achilles.
After Achilles' death Agamemnon and Menelaus award the hero's armour to Odysseus, driving Ajax the Greater to madness and suicide. At the fall of Troy Cassandra falls to Agamemnon as a prize of war.
III.Return, death, and the Atreid curse
On his return Clytemnestra, who had taken Aegisthus as lover, murdered Agamemnon — in Homer's Odyssey in a feasting hall under false hospitality, in Pindar and the tragedians in a bath, trapped in a net or robe. Cassandra was killed with him. Motives include revenge for Iphigenia and jealousy of Cassandra. Aegisthus and Clytemnestra then ruled until Orestes, urged by Electra, killed them and was pursued by the Erinyes until Athena and Apollo absolved him, ending the curse.
The family's miasma is traced to Tantalus, Pelops's murder of Myrtilus, and Atreus's crimes against Thyestes. In Peloponnesian legend Agamemnon was the type of the powerful monarch; Sparta worshipped him as Zeus Agamemnon. His fortunes became the subject of tragedy from Aeschylus's Oresteia onward, and he remains a figure in later literature from Shakespeare to Frank Herbert's House Atreides.