Economy of Belgium increased unemployment, stemming from the worldwide banking crisis. For 50 years through World War II, French-speaking Wallonia was a technically advanced, industrial region, with its industry concentrated along the sillon industriel, while Dutch-speaking Flanders was predominantly agricultural with some industry, mainly processing agricultural products and textiles. This disparity began to fade during the interwar period. When Belgium emerged from World War II with its industrial infrastructure relatively undamaged thanks to the Galopin doctrine, the stage was set for a period of rapid development, particularly in Flanders. The postwar boom years, enhanced by the establishment of the European Union and NATO
The Holocaust in Belgium the country before World War I. The interwar period saw substantial Jewish immigration to Belgium. By 1930, the population rose to 50,000, and by 1940 it was between 70,000–75,000. Most of the new Jewish immigrants came from Eastern Europe and Nazi Germany, escaping anti-Semitism and poverty in their native countries. The Roma population of Belgium at the same time was approximately 530. Few of the Jewish migrants claimed Belgian citizenship, and many did not speak French or Dutch. Jewish communities developed in Charleroi, Liège, Brussels and, above all, Antwerp, where more than half of the Jews in Belgium lived. The