The Trojan War was waged against the city of Troy by the Achaeans (Greeks) after Paris of Troy took Helen from her husband Menelaus, the king of Sparta.
Agamemnon, king of Mycenae and the brother of Helen's husband Menelaus, led an expedition of Achaean troops to Troy and besieged the city for ten years.
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, decisively ending the war.