The German occupation of Belgium during World War I lasted from August 1914 to November 1918. Numerous social relief movements were instituted; among them, the National Committee for Relief and Food had its headquarters in Brussels and, with U.S. aid, organized the feeding of the Belgian population. Adolphe de Max, the burgomaster of Brussels, acquired fame for his resistance to the abuses of the German occupiers. The Belgian army reoccupied the capital on Nov. 18, 1918, and four days later King Albert I and Queen Elisabeth reentered the city. After the war the administrative expansion of metropolitan Brussels that had begun in the 19th century continued. The area grew from 9 municipalities in 1878 to 16 in 1932 and to 19 in 1954. The metropolis, known as Greater Brussels, became an officially bilingual city in 1932.

In World War II, Brussels fell to the invading German army on May 18, 1940. The city did not suffer extensive physical damage but was subjected to harsh terms of occupation. To facilitate control Gen. Eggert Reeder, chief of the German military administration for Belgium, decided to follow the Nazi policy of creating large urban zones by amalgamating the communes. In order to crush the spirited opposition to this measure, Reeder dissolved all municipal councils and dismissed Joseph van de Meulebroeck, the leader of the opposition, from his post as burgomaster of Brussels. Reeder then appointed a governing council headed by Jan Grauls, a pro-Nazi Flemish nationalist. As in World War I, Germany tried to divide the nation by supporting partisans of Flemish autonomy. Although few Flemings actually collaborated with the enemy, anti-Flemish feelings ran high in metropolitan Brussels. The city was liberated on Sept. 3, 1944, by the British. Five days later the legitimate Belgian government returned to its capital from London.

After World War II, Brussels became decidedly more international, with the establishment of the headquarters of the European Communities (the predecessors of the European Union [EU]) in Brussels’s Léopold Quarter (1958) and the move of the NATO headquarters from Paris to the northeastern commune of Evere (1967). The city also was host to a successful world’s fair in 1958, which helped to rejuvenate the weakened postwar economy.

As the second half of the 20th century progressed, the Brussels region experienced suburbanization and deindustrialization, accompanied by the physical decline of the historic city centre. The city also stood at the centre of tensions between the Flemish and Walloon communities of Belgium. The Flemings pressed for effective bilingualism in the public services in Brussels itself and opposed any further expansion of the mainly French-speaking metropolis into neighbouring Flemish areas. Massive Flemish demonstrations against “Frenchification and territorial annexation” were held in the streets of Brussels in 1961 and 1962.

In an attempt to settle the issue, the Belgian parliament passed a law in 1963 that restricted the capital to its 19 officially bilingual municipalities but extended language facilities to French-speaking minorities in several suburban boroughs. The Francophone countermobilization against what was regarded as Flemish interference in city affairs led to the formation of the Brussels-based Francophone Democratic Front in 1964. Whereas the Flemings were intent on preventing the Francophone influence from spreading further, the French-speaking residents of Brussels resented the imposition of a legal carcan, or “straitjacket,” on the city. The front’s rapid growth gave it a firm political hold in the late 1970s, but its demise in the early 1980s was equally rapid, as the deepening national and international economic crisis drew attention away from the language conflict. The faltering economy also temporarily halted the reforms begun in 1962 devolving power from the central government to the communities and regions.

In the last decades of the 20th century, as a result of constitutional and administrative reform, Belgium became a federal state, with the Brussels-Capital Region established in 1989 as one of three autonomous regions, along with the regions of Flanders and Wallonia. Meanwhile, as the European Communities and their successor, the EU, expanded in size and scope, Brussels developed as the capital of the “new Europe,” hosting many of the EU’s institutions, including the European Commission, the Council of the European Union, the European Parliament (committee sessions), the European Economic and Social Committee, and the Committee of the Regions.

The 21st century

By the turn of the 21st century, modestly sized Brussels had mutated into one of the most significant cities in Europe, economically and politically. Brussels was located squarely inside the EU’s “blue banana” corridor, a highly developed economic region that extended, in the curved shape of a banana, from the southeastern United Kingdom, across parts of France, Belgium, the Netherlands, Germany, and Switzerland, into northern Italy. Moreover, the name Brussels had entered the public imagination as the preeminent icon of a powerful EU.

The international valorization of Brussels notwithstanding, the inner city—essentially the central, northern, and western communes of the agglomeration—was experiencing the deterioration of its infrastructure, reduced public services, falling numbers of middle-class residents, and a decline in private investment in enterprises and employment. Booming areas within the city—such as the neighbourhoods dominated by EU institutions—were experiencing a crisis of their own: the expulsion of local residents and nongovernmental businesses, the loss of local character, and unprecedented damage to the architectural patrimony of Brussels. Communes on the periphery of the Brussels-Capital Region attracted many among the middle class and the international cadre, thus reducing Brussels’s tax base.

The authorities’ response to these problems included a mixture of regulation, financial intervention, and public relations—such as a campaign to attract research and development enterprises to the city. Regional development plans met with some success in the revitalization of housing and the urban environment, integrated economic development, and the promotion of environmentally sustainable practices. For example, in 2002 the Brussels-Capital Region committed to a plan to improve air quality and to meet the requirements of international conventions on climate change. The Brussels authorities also focused on improving public safety, local and regional transportation, education, and public health. These efforts to reinvigorate Brussels, it was hoped, would enhance the city’s prosperity and complement its prestige as the acknowledged capital of Europe.

While some areas within the Brussels-Capital Region thrived thanks to these reforms, others, such as the Molenbeek district, continued to suffer from persistent high unemployment and limited social engagement. The fragmented nature of the capital area’s administrative structure—19 mayors oversaw six police departments, and language-based political patronage acted as a bottleneck on government services—meant that vulnerable residents often fell through the cracks. Terrorism experts noted that Molenbeek had produced a disproportionate number of foreign fighters participating in the Syrian Civil War, and attention was focused on the area in the wake of the November 13, 2015, terrorist attacks in Paris. It was believed that organizers of those attacks were Molenbeek natives, and the main surviving suspect, Salah Abdeslam, was captured there after four months at large.

On March 22, 2016, four days after Abdeslam’s arrest, Brussels was shaken by a trio of bomb blasts that claimed at least 30 lives and injured more than 250 people. A pair of bombs were detonated in the crowded check-in area of the main terminal at Brussels Airport, killing at least 10 and injuring 100. A little more than an hour later, a bomb exploded on a train as it departed the metro station at Maelbeek. Scores were injured and at least 20 people were killed in an attack that occurred just blocks from the headquarters of the European Commission and the Council of the European Union. European leaders rallied to express their solidarity with Brussels in the face of an assault on the very heart of the EU.