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North Atlantic Treaty Organization: Quick Facts

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Last updated

News •

Correction: Russia-Ukraine-War story • Nov. 13, 2026, 1:30 PM ET (AP)
US soldier assigned to NATO unit arrested in Britain on suspicion of espionage linked to Russia • Nov. 10, 2026, 4:38 PM ET (AP)
Romanian president calls alleged Russian sabotage plot a 'grave violation' of NATO member's security • Oct. 27, 2026, 5:00 PM ET (AP)
Drone strikes in the Black Sea raise fears of Russian escalation to test NATO's response • Oct. 16, 2026, 6:24 AM ET (AP)

Facts

Also Known As NATO • Organisation du Traité de l’Atlantique Nord • OTAN
Date April 4, 1949 - present
Areas Of Involvement Supreme Allied Commander Europe • defense • How does a country become a member of NATO?
Related People Dwight D. Eisenhower • Harry S. Truman • Konrad Adenauer • Mark Rutte • Joseph Dunford • John Shalikashvili • Eric K. Shinseki • Javier Solana • Ernest Bevin • Dean Acheson • Jaap de Hoop Scheffer • Rick Hillier • Willy Claes • Peter Carington, 6th Baron Carrington • Alcide De Gasperi

Did You Know?

  • No country that has joined NATO has ever opted to leave it.
  • The Russian occupation of the Crimean Peninsula in 2014 prompted NATO to cease cooperation with Russia.

Photos

Flag of NATO featuring a white compass rose emblem with four lines radiating from the center on a blue background.
World map highlighting NATO member countries in dark blue, Euro-Atlantic Partnership Council countries in light blue, NATO's Mediterranean Dialogue partners in purple, Istanbul Cooperation Initiative partners in pink, and global partners in teal. Brussels, Belgium, is marked as NATO headquarters. A timeline below the map shows the years each member joined NATO from 1949 to 2024.
Secretary of State Dean Acheson sits at a table signing the North Atlantic Pact as President Harry Truman and Vice President Alben Barkley stand behind him, with officials observing.
Map of Europe in 1960 during the Cold War, showing countries color-coded by political alignment: NATO members in green across Western Europe, Warsaw Pact countries in orange in Eastern Europe, and non-aligned nations in beige. The Soviet Union and its allies are grouped to the east, while Western European countries are aligned with the United States.
Kosovo conflict
flag-raising ceremony marking the accession of the Czech Republic, Hungary, and Poland to NATO
Jerzy Buzek, Miloš Zeman, Javier Solana, and Viktor Orbán at a ceremony marking the accession of the Czech Republic, Hungary, and Poland to NATO
Volodymyr Zelensky during the Russian invasion of Ukraine
Swedish Prime Minister Magdalena Andersson in a blue coat stands beside Finnish Prime Minister Sanna Marin in a black jacket outdoors before a meeting in Stockholm.
Secretary of State Dean Acheson, seated at a table holding a gavel, calls a NATO meeting to order, with T.A. Charlton on his left and Paul Van Zeeland in the foreground.
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