The United States has the second most active diplomatic posts of any country in the world after the People's Republic of China,^[1] including 271 bilateral posts (embassies and consulates) in 173 countries as well as 11 permanent missions to international organizations and seven other posts (as of November 2023^[2]). It maintains "interest sections" (in other states' embassies) in Afghanistan, Iran, North Korea, and Syria.

In December 1777, Morocco became the first nation to seek diplomatic relations with the United States and together they maintain the United States' longest unbroken treaty.^[3] Benjamin Franklin established the first overseas mission of the United States in Paris in 1779. On April 19, 1782, John Adams was received by the States-General and the Dutch Republic as they were the first country, together with Morocco and France, to recognize the United States as an independent government. John Adams then became the first U.S. ambassador to the Netherlands^[4][5][6][7] and the house that he had purchased there, at Fluwelen Burgwal 18 in The Hague, became the first U.S. embassy in the world.^[8]

In the period following the American Revolution, George Washington sent a number of close advisers, including Thomas Jefferson, John Adams, Francis Dana, and John Jay, to the courts of European potentates in order to garner recognition of U.S. independence, with mixed results.^[9]

The first overseas consulate of the fledgling United States was founded in 1790 in Liverpool, Great Britain, by James Maury Jr., who was appointed by Washington. Maury held the post from 1790 to 1829. Liverpool was at the time Britain's leading port for transatlantic commerce and therefore of great economic importance to the United States.^{[citation needed]} President George Washington, on November 19, 1792, nominated Benjamin Joy of Newbury Port as the first U.S. Consul to Kolkata (then Calcutta), India. Joy was not recognized as consul by the British East India Company but was permitted to "reside here as a Commercial Agent subject to the Civil and Criminal Jurisdiction of this Country."^[10] The United States' first owned overseas property is the American Legation in Tangier, which was a gift of the Sultan of Morocco in 1821.^[11][12] In general during the nineteenth century, the United States' diplomatic activities were done on a minimal budget.^{[additional citation(s) needed]} The U.S. owned no property abroad and provided no official residences for its foreign envoys, paid them a minimal salary, and gave them the rank of ministers rather than ambassadors who represented the great powers—a position which the U.S. only achieved towards the end of the nineteenth century.^[13]

In the latter half of the nineteenth century, the State Department was concerned with expanding commercial ties in Asia, establishing Liberia, foiling diplomatic recognition of the Confederate States of America during the American Civil War, and securing its presence in North America. The Confederacy had diplomatic missions in the United Kingdom, France, Belgium, the Papal States, Russia, Mexico, and Spain, and consular missions in Ireland, Canada, Cuba, Italy, Bermuda, and Nassau and New Providence.^[14]

The United States' global prominence became evident in the twentieth century, and the State Department was required to invest in a large network of diplomatic missions to manage its bilateral and multilateral relations.^[15] The wave of overseas construction began with the creation of the State Department's Foreign Service Buildings Commission in 1926.^[13]

•  Antigua and Barbuda^[655][656]
•  Kiribati^[657]
•  Cook Islands^[658]
•  Dominica^[659]
•  Libya^[660]
•  Niue^[658]
•  Vanuatu^[661]

• Ambassadors of the United States
• History of United States diplomatic relations by country
• List of countries by number of diplomatic missions
• List of diplomatic missions in the United States
• Terrorist attacks on U.S. diplomatic facilities
• United States Foreign Service
• Diplomatic Security Service