The XYZ Affair was a political and diplomatic episode in 1797 and 1798, early in the administration of John Adams, involving a confrontation between the United States and Republican France that led to an undeclared naval war called the Quasi-War. The name derives from the substitution of the letters X (Jean Hottinguer), Y (Pierre Bellamy) and Z (Lucien Hauteval) for the names of French diplomats in documents released by the Adams administration.
An American diplomatic commission was sent to France in July 1797 to negotiate problems that were threatening to break out into war.
The diplomats, Charles Cotesworth Pinckney, John Marshall, and Elbridge Gerry, were approached through informal channels by agents of the French Foreign Minister Talleyrand, who demanded bribes and a loan before formal negotiations could begin.
Although such demands were not uncommon in mainland European diplomacy of the time, the Americans were offended by them, and eventually left France without ever engaging in formal negotiations. Gerry, seeking to avoid all-out war, remained for several months after the other two commissioners left. His exchanges with Talleyrand laid groundwork for the eventual end to diplomatic and military hostilities.
The failure of the commission caused a political firestorm in the United States when the commission’s dispatches were published. It led to the undeclared Quasi-War (1798 to 1800). Federalists who controlled the government took advantage of the national anger to build up the nation’s military. They also attacked the Jeffersonian Republicans for their pro-French stance, and Elbridge Gerry (a nonpartisan at the time) for what they saw as his role in the commission’s failure.