Treaty of Alliance (1778)

The Treaty of Alliance with France or Franco-American Treaty was a defensive alliance between France and the United States of America, formed in the midst of the American Revolutionary War, which promised mutual military support in case fighting should break out between French and British forces, as the result signing the previously concluded Treaty of Amity and Commerce. The alliance was planned to endure indefinitely into the future. Delegates of King Louis XVI of France and the Second Continental Congress, who represented the United States at this time, signed the two treaties along with a separate and secret clause dealing with future Spanish involvement, at the hôtel de Coislin (4, place de la Concorde) in Paris on February 6, 1778. The Franco-American alliance that would technically remain in effect until the 1800 Treaty of Mortefontaine, despite being annulled by the United States Congress in 1793 when George Washington gave his Neutrality Proclamation speech saying that America would stay neutral in the French Revolution.

When the thirteen British colonies in America declared their independence from Great Britain in 1776, their most obvious potential ally was France, a long-time enemy of Britain and a colonial rival who had lost much of their lands in the Americas after the French and Indian War. France's leadership had been alarmed by Britain's victory in the Seven Years' War which had shifted the European balance of power and had been planning for a war of revenge since the Treaty of Paris that had ended the conflict in 1763. The French foreign minister Choiseul had envisaged this taking place in alliance with Spain and involving a Franco-Spanish invasion of Britain. Choiseul had been ready go to war in 1770 during the Falklands Crisis, but Louis XV had been alarmed by the British naval mobilization and instead dismissed Choiseul and backed down.

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