NATO's Expansion History

Department of Defense Photo Essay

  • For only the sixth time in its 59-year history, NATO is poised to expand its membership this week. At the alliance‚Äôs three-day summit conference officials are expected to extend an invitation to Albania, Croatia and Macedonia for NATO membership. 

After the original North Atlantic Treaty was signed April 4, 1949, in Washington, D.C.,
Greece and Turkey became the next countries to join NATO in 1952, signing accession documents, such as the one seen here,  that became part of the treaty. Photo courtesy of NATO
  • The Federal Republic of Germany becomes a member of NATO at the summit in Paris, France, May 6, 1955. After signing the accession documents, German Chancellor Konrad Adenauer takes his seat at the NATO Council table.
 Photo courtesy of NATO
  • Spain's accession ceremony is held at NATO Headquarters in Brussels, Belgium, June 5, 1982. J.P. Llorca, left, Spain's Minister of Foreign Affairs, joins NATO Secretary General. J. Luns, right, at the NATO Council table.
 Photo courtesy of NATO
  • Spain's flag joins those of other NATO nations in front of the NATO headquarters building in at NATO Headquarters in Brussels, Belgium, June 5, 1982, in the ceremonies celebrating Spain's accession to NATO. Photo courtesy of NATO
  • Left to right: Polish Prime Minister J. Buzek, Czech Republic President M. Zeman,  NATO Secretary General Dr. J. Solana and Hungarian Prime Minister. V. Orban observe flag-raising ceremonies celebrating the accession of Poland, the Czech Republic and Hungary to NATO, March 16, 1999, at NATO's headquarters in Brussels, Belgium. Photo courtesy of NATO
  • The flag of the Czech Republic is raised during a ceremony outside of NATO's Brussels, Belgium, headquarters following the country's accession to NATO, March 16, 1999.
 Photo courtesy of NATO
  • The Hungarian flag is raised during a ceremony outside of NATO's Brussels, Belgium, headquarters, where the flags of all member nations are flown, following the country's accession to NATO, March 16, 1999.
 Photo courtesy of NATO
  • The Polish flag is raised during a ceremony outside of NATO's Brussels, Belgium, headquarters, where the flags of all member nations are flown, following the country's accession to NATO, March 16, 1999.
 Photo courtesy of NATO
  • In its largest accession ceremony to date, NATO invited Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia and Slovenia to sign the North Atlantic Treaty during a meeting in Washington, D.C., March 29, 2005. 

Left to right: Slovenian Prime Minister Anton Rop; Slovakian Prime Minister Milkulas Dzurinda; Romanian Prime Minister Adrian Nastase; Lithuanian Prime Minister Algirdas Brazaukas; Latvian Prime Minister Indulis Emsis; Estonian Prime Minister Juhan Parts; and Bulgarian Prime Minister Simeon Saxe-Coburg Gotha prepare to speak to the press after the accession ceremony. Photo courtesy of NATO
  • Leaders of the seven new NATO Members -  Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia and Slovenia -  and Albania, Croatia and Macedonia, which are candidates for NATO membership, meet U.S. President George W. Bush at the White House in Washington, D.C., March 29, 2004. 

Having participated in NATO's membership action plan, Albania, Croatia and Macedonia in the ensuing four years, are expected to be invited to join NATO at the Bucharest Summit April 2-4, 2008.
 Photo courtesy of NATO