France attacked U.S. ship full of goods being exported to Great Britain. After the Jay Treaty was ratified between the UK and the U.S., France saw this actions as violation of their past treaties. John Adams sent a three men delegate to try to solve the problem between the U.S and France as an attempt to stop the attacks. France's secretary of foreign affairs didn't meet with the three delegates because he would only do so if the U.S pay France, basically a bribe! After the U.S. didn't agree to this, John Adams sent the report of the event to congress. Instead of spelling out the names of the parties involved, Adams wrote XYZ in the report; and that's the reason why the affair is known as the XYZ Affair. When the U.S heard of the demands made by France, they called for war. Congress authorized American ships to attack French vessels, which started an undeclared war referred to as the Quasi-War. It all ended after the Treaty of Mortefontaine ratified by the U.S in 1801.