History of Belgium on matters of religion and, in recent decades, it has faced new divisions over differences of language and unequal economic development. This ongoing antagonism has caused far-reaching reforms since the 1970s, changing the formerly unitary Belgian state into a federal state, and repeated governmental crises. It is now divided into three regions: Flanders (Dutch-speaking) in the north, Wallonia (French-speaking) in the south, and bilingual Brussels in the middle. There is also a German-speaking population along the border with Germany that was granted to Prussia in the Congress of Vienna in 1815 but added to Belgium following the 1919 Treaty of
Languages of Belgium enjoy official status. Article 4 does however divide the country into linguistic areas, which form the basis of the federal structure: "Belgium has four linguistic areas: The French-speaking area, the Dutch-speaking area, the bilingual area of Brussels Capital and the German-speaking area." Before the federal structure and the language legislation gradually introduced in the 20th century, French was generally the only language used by public authorities. For example, the Dutch version of the Constitution has enjoyed equal status to the original French one only since 1967, and the German version only since 1991. Of the inhabitants of Belgium, roughly 59%