The Battle of Saratoga helped persuade France to ally with the United States during the American Revolutionary War.
The Saratoga campaign culminated in two battles in New York on September 19 and October 7, 1777. American forces eventually forced British General John Burgoyne to surrender his army on October 17.
The victory demonstrated that the American rebellion could defeat a major British field force. France had already provided secret aid, but Saratoga made formal cooperation more attractive because it showed that Britain might actually lose the war.
France signed the Treaty of Amity and Commerce and the Treaty of Alliance with the United States in February 1778. French money, weapons, soldiers, and naval forces later became crucial, especially during the Yorktown campaign. Saratoga is therefore commonly described as a turning point, though the war continued for several more years after the victory.