Agamemnon was the son of King Atreus and Queen Aerope of Mycenae and was considered the leader, or commander-in-chief, of the Greeks during the Trojan War. Menelaus was his younger brother, and he was married to Helen of Troy, who was the supposed cause of the war, being the most beautiful woman in the world.
In book 3 of Homer's epic poem, The Odyssey, the answer to the question of what Agamemnon and Menelaus are fighting about can be found in lines 102-147. In this section, Nestor is responding to the plea of Telemachus to tell him information about his father, Odysseus, whom Telemachus assumes has died. Nestor speaks highly of Odysseus and his cleverness in battle, and then recounts the sacking of King Priam's citadel.
Nestor goes on to describe the trouble that they had after this. He says that some of the men acted unjustly, and stirred the wrath of the gods. He describes the quarrel between the brothers Agamemnon and Menelaus as one that was instigated by Athena, who was angry...
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