History of NATO

The history of the North Atlantic Treaty Organization (NATO) begins in the immediate aftermath of World War II. In 1947, the United Kingdom and France signed the Treaty of Dunkirk and the United States set out the Truman Doctrine, the former to defend against a potential German attack and the latter to counter Soviet expansion. The Treaty of Dunkirk was expanded in 1948 with the Treaty of Brussels to add the three Benelux countries (Belgium, the Netherlands, and Luxembourg) and committed them to collective defense against an armed attack for fifty years. The Truman Doctrine expanded in the same year, with support being pledged to oppose the communist rebellions in Greece and Czechoslovakia, as well as Soviet demands from Turkey. In 1949, the NATO defensive pact was signed by twelve countries on both sides of the North Atlantic – the five Brussels signatories, the United States, Canada, Italy, Portugal, Norway, Denmark, and Iceland.^[1] Greece and Turkey joined in 1952, West Germany joined in 1955, Spain joined in 1982, Czech Republic, Hungary and Poland joined in 1999, Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia, and Slovenia joined in 2004, Albania and Croatia joined in 2009, Montenegro joined in 2017, North Macedonia joined in 2020, Finland joined in 2023, and Sweden joined in 2024.

The structure of NATO evolved throughout the Cold War and its aftermath. An integrated military structure for NATO was first established in 1950 as it became clear that NATO would need to enhance its defences for the longer term against a potential Soviet attack. In April 1951, Allied Command Europe and its headquarters (SHAPE) were established; later, four subordinate headquarters were added in Northern and Central Europe, the Southern Region, and the Mediterranean.^[2]

From the 1950s to 2003, the Strategic Commanders were the Supreme Allied Commander Europe (SACEUR) and the Supreme Allied Commander Atlantic (SACLANT).