Belgium–Luxembourg Economic Union Belgium–Luxembourg Economic Union The Belgium–Luxembourg Economic Union (, , ), abbreviated to BLEU or UEBL, is an economic union between Belgium and Luxembourg, two countries in the Benelux Union. BLEU was created by a treaty, signed on 25 July 1921, despite a referendum against such a proposal, between Belgium and Luxembourg, and came into effect upon ratification by the Luxembourg Chamber of Deputies on 22 December 1922. Under the terms of the treaty, the economic frontier was lifted and the Belgian franc and Luxembourg franc were set at a fixed parity (though revised in 1935 and 1944) establishing a monetary
Southern Netherlands Orange at the 1815 Congress of Vienna. The southeastern third of Luxembourg Province was made into the autonomous Grand Duchy of Luxembourg, because it was claimed by both the Netherlands and Prussia. In 1830 the predominantly Roman Catholic southern half became independent as the Kingdom of Belgium (the northern half being predominantly Calvinist). In 1839 the final border between the kingdom of the Netherlands and Belgium was determined and the eastern part of Limburg returned to the Netherlands as the province of Limburg. The autonomy of Luxembourg was recognised in 1839, but an instrument to that effect was not signed