The
Franco-American alliance refers to the 1778 alliance between the
Kingdom of
France and the
United States during the
American Revolutionary War. Formalized in the 1778
Treaty of Alliance, it was a military pact in which the French provided many supplies for the Americans. The
Netherlands and
Spain later joined as allies of France; Britain had no allies. The French alliance was possible once the Americans captured a British invasion army at
Saratoga in October 1777, demonstrating the viability of the American cause. The alliance became controversial after 1793 when Britain and
Revolutionary France again went to war and the U.S. declared itself
neutral. Relations between France and the United States worsened as the latter became closer to Britain in the
Jay Treaty of 1795, leading to an undeclared
Quasi War. The alliance was defunct by 1794 and formally ended in 1800.