Timeline of NATO expansion since 1949


              FILE - NATO Secretary General Jens Stoltenberg, center, participates in a media conference with Finland's Foreign Minister Pekka Haavisto, left, and Sweden's Foreign Minister Ann Linde, right, at NATO headquarters in Brussels, Monday, Jan. 24, 2022. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Olivier Matthys, File)
            
              FILE - Soldiers from Montenegro unfurl the national flag during a ceremony to mark the accession of Montenegro at NATO Headquarters in Brussels on Wednesday, June 7, 2017. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Virginia Mayo, File)
            
              FILE - A Romanian IAR99 fighter jet fires its canons during a joint NATO US-Romanian military exercise in Cincu, central Romania, Thursday, Sept. 25, 2014. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Vadim Ghirda, File)
            
              FILE - An Albanian NATO symbol set up at Mother Teresa Square as preparations continue for the country's membership into the alliance in Tirana Saturday, April 4, 2009. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Hektor Pustina, File)
            
              FILE - NATO leaders and delegates take part in a session with invitees, at the NATO Summit conference in Bucharest, Thursday April 3, 2008. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Vadim Ghirda, File)
            
              FILE - British peacekeeper Pvt. Sean Knight of Petersbourough talks with Afghan children during a stop while patrolling a village in Kabul, Afghanistan Tuesday, Aug. 12, 2003, a day after NATO took over command of the 5,000-strong of the ISAF. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Apichart Weerawong, File)
            
              FILE - Russian president Vladimir Putin, left, and President Bush share a word at the end of the signing ceremony for the NATO Russia summit in the Pratica di Mare Air Force base on the outskirts of Rome, Tuesday May 28, 2002. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Andrew Medichini)
            
              FILE - Hungarian T-72 armoured tanks during a military drill in the Bakony Hill in Veszprem Country. Hungary, Poland, and the Czech Republic will become full members of the North Atlantic Treaty Organization (NATO) on March 12, 1999. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/File)
            FILE - Members of the 82nd Airborne Division of the U.S. Army clean weaponry ahead of deployment to Poland from Fort Bragg, N.C. on Monday, Feb. 14, 2022. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Nathan Posner, File) FILE - Top generals of the Warsaw Treaty shake hands during a meeting in Moscow, Soviet Union, Monday March 25, 1991. From left to right: Rumanian Mircea Constantinescu; Bulgarian Penyu Kostadinov; Soviet General Vladimir Lyubov; Hungarian Robert Seles; and Czech Michal Gondech, met for the last time, as the treaty will be dissolved March 31, 1991. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/File) FILE - An anti-NATO protester making a mocking gesture to a poster with a photograph of U.S. President George W. Bush while rallying at the central Independence square to protest Bush's visit and Ukraine's efforts to join NATO in Kiev, Ukraine, Monday, March 31, 2008. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Ivan Sekretarev, File) FILE - French President Emmanuel Macron, center, puts his arm on the shoulder of U.S. President Joe Biden, center left, and British Prime Minister Boris Johnson as they speak at a group photo during an extraordinary NATO summit at NATO headquarters in Brussels, Thursday, March 24, 2022. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Thibault Camus, File) FILE - Paratroopers take part in an exercise of the U.S. Army Global Response Force in Hohenfels, Germany, Wednesday, Aug. 26, 2015. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Matthias Schrader, File) 
              FILE - Secretary of State Dean Acheson signs the Atlantic defense treaty for the United States, April 4, 1949. Vice President Alben W. Barkley, left, and President Harry Truman converse during the signing. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/File)
            FILE - U.S. soldiers part of the NATO- led International Security Assistance Force (ISAF) walks, as a U.S. Chinook helicopter is seen on the back ground near the place where the foundation of a hospital was laid in Shindand, Herat, west of Kabul, Afghanistan, Saturday, Jan. 28, 2012. Finland and Sweden are nearing decisions on whether to ditch their long-standing policy of military nonalignment and join NATO in the wake of Russia's invasion of Ukraine. Finnish President Sauli Niinisto is expected to announce his stance on NATO membership on Thursday, May 12, 2022. (AP Photo/Hoshang Hashimi, File)