The Continental Congress of the United States of America sent John Jay to Spain in 1779 in an attempt to convince the Spanish Court to recognize the new nation. Jay spent two years there to no success, but Spain recognized the United States in 1783. Since then the two countries have broken relations just once, when they went to war against each other in the Spanish-American War of 1898. Currently Spain is a constitutional monarchy, a member of the European Union and the North Atlantic Treaty Organization (NATO).
Spain and the United States are closely associated in many fields. Spain joined NATO in 1982. In addition to U.S. and Spanish cooperation within NATO, defense and security relations between the two countries are regulated by the Mutual Defense Assistance Agreement and the Agreement on Defense Cooperation. Under this agreement, Spain has authorized the United States to use certain facilities at Spanish military installations.
The two countries have a cultural and educational cooperation agreement. The U.S. embassy conducts educational, professional, and cultural exchange programs. Spain is the third most popular destination for U.S. students worldwide. The binational Fulbright program for graduate students, postdoctoral researchers, and visiting professors is among the largest in the world.
The U.S. Ambassador to Spain is also accredited as Ambassador to Andorra. The U.S. Consul General based in Barcelona is responsible for the day-to-day management of relations with Andorra, and travels regularly to Andorra to carry out diplomatic demarches, represent U.S. interests, promote U.S. business, and administer consular services as needed. Today, the U.S. embassy in Spain is in Madrid. For more information on our relationship with Spain, please click here. For more information on our relationship with Andorra, please click here.
Source, United States Department of State, Office of the Historian and Bureau of European and Eurasian Affairs.