Paris, who was a Troyan Prince disguised as a peasant, was chosen by Zeus, to decide which one of all the goddesses of the Olymp who was the most beautiful. His final chose was between Hera, Zeus' wife, Athena, goddess of war and wisdom and Aphrodite, the goddess of love. Aphrodite became the winner. She was given an apple as reward. That was the snowball which became the avalanche of the Troyan war.