In Greek mythology, the Trojan War was waged against the city of Troy by the Achaeans (Greeks) after Paris of Troy took Helen from her husband Menelaus, king of Sparta.

The war originated from a quarrel between the goddesses Hera, Athena, and Aphrodite, after Eris, the goddess of strife and discord, gave them a golden apple, sometimes known as the Apple of Discord, marked "for the fairest". Zeus sent the goddesses to Paris, who judged that Aphrodite, as the "fairest", should receive the apple. In exchange, Aphrodite made Helen, the most beautiful of all women and wife of Menelaus, fall in love with Paris, who took her to Troy.

Agamemnon, king of Mycenae and the brother of Helen's husband Menelaus, led an expedition of Achaean troops to Troy. After a fruitless 10-year siege, the Greeks constructed a huge wooden horse, and hid a select force of men inside. The Greeks pretended to sail away, and the Trojans pulled the horse into their city as a victory trophy. That night the Greek force crept out of the horse and opened the gates for the rest of the Greek army, which had sailed back under cover of night. The Greeks entered and destroyed the city of Troy, ending the war.

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