The U.S. established diplomatic relations with Spain in 1783. Spain severed diplomatic relations with the U.S. in 1898 at the start of the Spanish-American War, in which Spain lost Puerto Rico, Guam, and the Philippines to the U.S. U.S.-Spanish relations were reestablished in 1899.
Bilateral Economic Relations
Spain's accession to the European Union (EU) in 1986 required the country to open its economy to trade and investment, modernize its industrial base, improve infrastructure, and revise economic legislation to conform to EU guidelines. Spain is the fifth-largest economy in the EU and the fourth-largest economy in the Eurozone. Spain and the U.S. have a friendship, navigation, and commerce treaty and a bilateral taxation treaty. Many U.S. companies channel their Spanish investments and operations through third countries.