The Treaty of Brussels, also referred to as the Brussels Pact, was the founding treaty of the Western Union (WU) between 1948 and 1954, when it was amended as the Modified Brussels Treaty (MTB) and served as the founding treaty of the Western European Union (WEU) until its termination in 2010. The treaty provided for the organisation of military, economic, social and cultural cooperation among member states as well as a mutual defence clause.

The treaty was signed on 17 March 1948 by Belgium, France, Luxembourg, the Netherlands and the United Kingdom, the members of the Western Union, as an expansion to the Treaty of Dunkirk, which had been signed between Britain and France the previous year to guard against possible German or Soviet aggression after the end of World War II.

The need to back up the commitments of the North Atlantic Treaty with appropriate political and military structures led to the creation of the North Atlantic Treaty Organisation (NATO). In December 1950, the parties to the Treaty of Brussels decided to transfer the headquarters, personnel and plans of the Western Union Defence Organisation (WUDO) to NATO, whose Supreme Headquarters Allied Powers Europe (SHAPE) took over responsibility for the defence of Western Europe.The establishment of NATO, along with the signing of a succession of treaties establishing the Organisation for European Economic Cooperation (April 1948), the Council of Europe (May 1949) and the European Coal and Steel Community (April 1951), left the Treaty of Brussels and its Western Union devoid of authority.

The treaty was amended at the 1954 Paris Conference as a result of the failure of the Treaty establishing the European Defence Community to gain French ratification: The General Treaty (German: Deutschlandvertrag) of 1952 formally named the EDC as a prerequisite of the end of Allied occupation of Germany, and there was a desire to include Germany in the Western defence architecture. The Modified Brussels Treaty (MBT) transformed the Western Union into the Western European Union (WEU), at which point Italy and Germany were admitted. Although the WEU that was established by the Modified Brussels Treaty was significantly less powerful and ambitious than the original Western Union, German membership of the WEU was considered sufficient for the occupation of the country to end in accordance with the General Treaty.

When the European Union (EU) gained its own mutual defence clause upon the entry into force of the Treaty of Lisbon in 2009, the members of the WEU, which were also EU member states, regarded the WEU as redundant. Consequently, the Modified Treaty of Brussels was terminated on 31 March 2010, followed by the closure of WEU bodies on 30 June 2011.



Belgium, officially the Kingdom of Belgium, is a country in Western Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to the southwest, and the North Sea to the northwest. It covers an area of 30,689 km2 (11,849 sq mi) and has a population of more than 11.5 million, making it the 22nd most densely populated country in the world and the 6th most densely populated country in Europe, with a density of 376 per square kilometre (970/sq mi). The capital and largest city is Brussels; other major cities are Antwerp, Ghent, Charleroi, Liège, Bruges, Namur, and Leuven.

Belgium is a sovereign state and a federal constitutional monarchy with a parliamentary system. Its institutional organization is complex and is structured on both regional and linguistic grounds. It is divided into three highly autonomous regions: the Flemish Region (Flanders) in the north, the Walloon Region (Wallonia) in the south, and the Brussels-Capital Region. Brussels is the smallest and most densely populated region, as well as the richest region in terms of GDP per capita.

Belgium is home to two main linguistic communities: the Dutch-speaking Flemish Community, which constitutes about 60 percent of the population, and the French-speaking Community, which constitutes about 40 percent of the population. A small German-speaking Community, numbering around one percent, exists in the East Cantons. The Brussels-Capital Region is officially bilingual in French and Dutch, although French is the dominant language. Belgium's linguistic diversity and related political conflicts are reflected in its complex system of governance, made up of six different governments.

The country as it exists today was established following the 1830 Belgian Revolution, when it seceded from the Netherlands, which had itself only existed since 1815. The name chosen for the new state is derived from the Latin word Belgium, used in Julius Caesar's "Gallic Wars", to describe a nearby region in the period around 55 BCE. Belgium is part of an area known as the Low Countries, historically a somewhat larger region than the Benelux group of states, as it also included parts of northern France. Since the Middle Ages, its central location near several major rivers has meant that the area has been relatively prosperous, connected commercially and politically to its bigger neighbours. Belgium has also been the battleground of European powers, earning the moniker the "Battlefield of Europe", a reputation strengthened in the 20th century by both world wars.

Belgium participated in the Industrial Revolution and, during the course of the 20th century, possessed a number of colonies in Africa. Between 1885 and 1908, the Congo Free State, which was privately owned by King Leopold II of Belgium, was characterized by widespread atrocities and a population decline of millions, leading Belguim to takeover the territory as a colony.The second half of the 20th century was marked by rising tensions between the Dutch-speaking and the French-speaking citizens fuelled by differences in language and culture and the unequal economic development of Flanders and Wallonia. This continuing antagonism has led to several far-reaching reforms, resulting in a transition from a unitary to a federal arrangement during the period from 1970 to 1993. Despite the reforms, tensions between the groups have remained, if not increased; there is significant separatism particularly among the Flemish; controversial language laws exist such as the municipalities with language facilities; and the formation of a coalition government took 18 months following the June 2010 federal election, a world record. Unemployment in Wallonia is more than double that of Flanders, which boomed after the Second World War.Belgium is one of the six founding countries of the European Union and its capital, Brussels, hosts the official seats of the European Commission, the Council of the European Union, and the European Council, as well as one of two seats of the European Parliament (the other being Strasbourg). Belgium is also a founding member of the Eurozone, NATO, OECD, and WTO, and a part of the trilateral Benelux Union and the Schengen Area. Brussels hosts the headquarters of many major international organizations such as NATO.Belgium is a developed country, with an advanced high-income economy. It has very high standards of living, quality of life, healthcare, education, and is categorized as "very high" in the Human Development Index. It also ranks as one of the safest or most peaceful countries in the world.