Belgium

The territory of present-day Belgium was inhabited in antiquity by tribes that the Romans grouped under the name Belgae, a confederation of Celtic and partly Germanic peoples whom Julius Caesar described in the first century BCE during his conquest of Gaul. Roman rule organised the region as part of Gallia Belgica, bringing roads, towns, and Latin culture, before the imperial frontier collapsed under successive incursions. From the late Roman period through the early medieval centuries, the Salian Franks settled the northern lowlands and gave rise to the Merovingian and then Carolingian dynasties, under which Charlemagne, crowned in 800, ruled an empire whose heartland lay close to the Meuse valley. The Treaty of Verdun in 843 divided that empire, leaving the Belgian lands split between West Francia and the Middle Kingdom, a fracture that shaped later regional identities.

During the High and Late Middle Ages, the region fragmented into a patchwork of prosperous principalities, including the County of Flanders, the Duchy of Brabant, the Bishopric of Liege, and the County of Hainaut, whose textile towns such as Bruges, Ghent, and Ypres became among the wealthiest in northern Europe. Through marriage and inheritance these territories were gathered in the fifteenth century under the Dukes of Burgundy, and on the extinction of that line passed to the Habsburgs. The Reformation and the Dutch Revolt in the late sixteenth century split the Low Countries: the northern provinces broke away as the Dutch Republic, while the southern provinces, the future Belgium, remained Catholic and under Spanish, and after 1714 Austrian, Habsburg rule. French revolutionary armies annexed the territory in 1795, and after Napoleon's defeat the Congress of Vienna in 1815 attached it to the new United Kingdom of the Netherlands.

Tensions over religion, language, and political representation produced the Belgian Revolution of 1830, and a National Congress proclaimed an independent constitutional monarchy. The Treaty of London in 1839 secured international recognition and guaranteed Belgian neutrality, with Leopold I of Saxe-Coburg and Gotha as the first king. The young state industrialised rapidly and acquired a vast colonial possession when Leopold II took personal control of the Congo Free State in 1885; international outcry over abuses led the Belgian parliament to annex the territory as the Belgian Congo in 1908. German invasions in 1914 and 1940 broke the country's neutrality, and the Second World War left lasting questions about the wartime conduct of King Leopold III, culminating in his abdication in 1951.

Postwar Belgium became a founding member of the Benelux customs union, NATO, and the European Coal and Steel Community, anchoring it firmly in Western European integration. Decolonisation saw Congo gain independence in 1960, followed by Rwanda and Burundi in 1962. Internally, persistent friction between the Dutch-speaking Flemish north and French-speaking Walloon south drove a long process of constitutional reform between 1970 and 1993 that converted the unitary kingdom into a federal state with linguistic communities and regions, including a bilingual Brussels-Capital Region.

Today Belgium is a federal parliamentary constitutional monarchy whose head of state, since 2013, is King Philippe, with executive power exercised by a federal government accountable to a bicameral parliament and shared with the country's communities and regions. Brussels also serves as a principal seat of the European Union and the headquarters of NATO.