This poem is based on the myth, "The Judgement of Paris," in which a Trojan prince was required to choose the most worthy of three goddesses: Hera, Athena, and Aphrodite.  The prize for the fairest goddess was the Golden Apple, an essentially worthless trinket used by the goddess of discord, Eris, to exact her revenge on the Pantheon.  Each goddess offered Paris a gift in exchange for the Golden Apple: control over all of Europe and Asia, wisdom, and the most beautiful woman in the world.  He chose the latter offering, Aphrodite's  promise.  The woman was Helen of Sparta, later to become the infamous Helen of Troy.  This exchange was said to be the catalyst of the Trojan War.