History of Belgium from Korea in 1955. On September 5, 1944, the Benelux Customs Union was created. It entered into force in 1948, and ceased to exist on 1 November 1960, when it was replaced by the Benelux Economic Union after a treaty signed in The Hague on February 3, 1958. The Benelux Parliament was created in 1955. The Treaty of Brussels, signed on 17 March 1948 by Belgium, the Netherlands, Luxembourg, France, and the United Kingdom, is considered the precursor to the NATO agreement, which Belgium became an official member of on April 4, 1949. The headquarters of NATO are located in
Luxembourg (Belgium) Luxembourg (Belgium) Luxembourg (; ; ; ; ) is the southernmost province of Wallonia and of Belgium. It borders on (clockwise from the east) the country of Luxembourg, France, and the Belgian provinces of Namur and Liège. Its capital is Arlon (, ), in the south-east of the province. It has an area of , making it the largest Belgian province. At around 250,000 residents, it is also the least populated province, making it a relatively sparsely populated province in an otherwise very densely populated country. It is significantly larger (70%) and much less populous than the neighbouring Grand Duchy