The Battle of Ko Chang took place on 17 January 1941 during the Franco-Thai War and resulted in a decisive victory by the French over the Royal Thai Navy. During the battle, a flotilla of French warships attacked a smaller force of Thai vessels, including a coastal battleship. In the end, Thailand lost two ships sunk and one heavily damaged and grounded. Within a month of the engagement, the Vichy French and the Thais negotiated a peace which ended the war.