The outcome was byzantine in its complexity. Belgium was sub-divided into three “Regions”: Flanders, Wallonia and “Brussels-Capital”, each with its own elected parliament (in addition to the national parliament). Then there were the three formally instituted “Communities”: the Dutch-speaking, the French-speaking and the German-speaking (the latter representing the approximately 65,000 German speakers who live in eastern Wallonia near the German border). The communities, too, were assigned their own parliaments.
The regions and the linguistic communities don’t exactly correspond — there are German speakers in Wallonia and a number of French-speaking towns (or parts of towns) within Flanders. Special privileges, concessions, and protections were established for all of these, a continuing source of resentment on all sides. Two of the regions, Flanders and Wallonia, are effectively unilingual, even with the exceptions noted. Brussels was prounced officially bilingual, even though at least 85 percent of the population speaks French.
In addition to the regional and linguistic Communities, Belgium was also divided into ten provinces (five each in Flanders and Wallonia). These, too, were assigned administrative and governing functions. But in the course of the various constitutional revisions real authority came increasingly to lie either with the regions (in matters of urbanism, environment, the economy, public works, transport and external commerce) or the linguistic community (education, language, culture and some social services).
The outcome of all these changes was comically cumbersome. Linguistic correctness (and the constitution) now required, for example, that all national governments, whatever their political color, be “balanced” between Dutch- and French-speaking ministers, with the prime minister the only one who has to be bilingual (and who is therefore typically from Flanders). Linguistic equality on the Cour d’Arbitrage (Constitutional Court) was similarly mandated, with the presidency alternating annually across the language barrier. In Brussels, the four members of the executive of the capital region would henceforth sit together (and spake in the language of their choice) to decide matters of common concern; but for Flemish or Francophone “community” affairs they would sit separately, two by two.
As a consequence Belgium was no longer one, or even two, states but an uneven quilt of overlapping and duplicating authorities. To form a government was difficult: it required multi-party deals within and across regions, “symmetry” between national, regional, community, provincial, and local party coalitions, a working majority in both major language groups and linguistic parity at every political and administrative level. And when a government was formed it had little initiative: even foreign policy — in theory one of the last remaining responsibilities of the national government — was effectively in the hands of the regions, since for contemporary Belgium it mostly means foreign trade agreements and these are a regional prerogative.
Tony Judt, “The Old Europe — and the New”, Postwar: A History of Europe Since 1945, 2005.