While anchored off Jamaica in 1504, Christopher Columbus found himself in dire straits. Though his supplies were running low, the Jamaican Indians refused to sell him any more food. Consulting his almanac, Columbus noticed that a lunar eclipse was due a few days later. On the appointed day, he summoned the Jamaican leaders and warned them that he would blot out the moon that very evening if his demands for food were not promptly met. The Jamaicans only laughed at him -- until later that night when the eclipse began. As the moon disappeared before their eyes, they visited Columbus in a state of terror, whereupon he agreed to stop his magic in exchange for food. The offer was accepted and the moon "restored."
[On May 28, 585 BC, the armies of Lydia and Media, preparing to engage in battle (in Asia Minor), were suddenly interrupted by a solar eclipse. Sobered by the event, the adversaries promptly signed a peace treaty and went home. The incident remains the oldest historical event which can be precisely dated.]