XYZ Affair, a diplomatic controversy between the United States and France, 1797–98, that led to an undeclared naval war. While France and Great Britain were at war in the 1790's, Britain and the United States signed a treaty (the Jay Treaty, in 1795) to settle mutual differences. The French took offense at a provision in the treaty that closed United States ports to their privateers and retaliated by seizing American ships. President John Adams dispatched Charles Cotesworth Pinckney, John Marshall, and Elbridge Gerry to Paris to negotiate a settlement.
The French government refused to officially receive the American delegation. Instead, Talleyrand, the French foreign minister, secretly sent three agents to the commissioners. They demanded a bribe for Talleyrand and a loan for France in order to stop the shipping raids. The Americans refused their demands. (Pinckney is said to have replied, "No! No! Not a sixpence!" A variation of his response—"Millions for defense, but not one cent for tribute"—later became a patriotic rallying cry.)
Adams submitted to Congress the commissioners' correspondence detailing the incident and referring to the French agents as X, Y, and Z. The story of the Americans' treatment by France caused a public uproar, and the United States prepared for war. Congress repealed the treaties of friendship and alliance signed with France in 1778. In an undeclared naval war that followed (1798–1800), several battles were fought, and French ships were captured. France hastened to negotiate a settlement of the dispute. This was done in the "Commission of Peace, Commerce, and Navigation," signed in 1800.
