Enlargement of NATO
Czechia, Hungary, and Poland formally join NATO
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Original prompt & settings (JSON) ↗The documents that redrew Europe's military map changed hands in a Missouri town called Independence, inside Harry Truman's presidential library.
Three instruments, deposited in Missouri
On 12 March 1999, at the Harry S. Truman Presidential Library in Independence, Missouri, the Czech, Hungarian and Polish foreign ministers deposited their countries' instruments of accession to the North Atlantic Treaty with the United States, the treaty's depositary.
Jan Kavan, János Martonyi and Bronisław Geremek handed them over; Secretary of State Madeleine Albright received them. The recorded ceremony ran 60 minutes.
Czechoslovak-born Albright marked the moment with one word: “Hallelujah.”
Membership from the moment of deposit
Deposit of the instruments made the three states NATO members, taking the Alliance from 16 countries to 19.
Accession runs through Article 10 of the North Atlantic Treaty, which required each state to become a party by depositing an instrument with the U.S. government once existing members had ratified the accession protocols and the invitees had completed their domestic procedures.
Article 14, which a NATO news caption associated with the ceremony, concerns custody of the treaty text instead.
The photographed moment came four days later
The flags went up at NATO headquarters in Brussels on 16 March, alongside the first special North Atlantic Council meeting of 19 allies. The legal accession had already happened in Missouri.
NATO calls these the first former Warsaw Pact members to join. The former East German Länder had come under NATO through German reunification in 1990, but East Germany did not accede as a surviving independent state.
Nor did the Soviet Union dissolve the year after the Warsaw Pact ended: both happened in 1991, the USSR formally ceasing to exist on 26 December.
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Researched 24 Aug 2026 6 sources not yet audited
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