28th May 585 BCE: Eclipse of Thales ends the Battle of Halys between Media and Lydia

A solar eclipse during the Battle of Halys led to a truce between the kingdoms of Media and Lydia, making it the earliest historical event that can be precisely dated.

29th February 1504: Christopher Columbus uses knowledge of a lunar eclipse to secure supplies while stranded on Jamaica

Christopher Columbus used knowledge of a forthcoming lunar eclipse to fool Jamaican natives into providing his stranded crew with provisions.