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
Provinces of Belgium and Luxembourg, as well as parts of modern Germany and France, comprised a number of rival and independent feudal states of varying sizes. These each had their own identities and governments, though in the early modern period almost all the Belgian states became part of larger entities (the Seventeen Provinces (1549-1581) and the Southern Netherlands (after 1581)). Prominent early states in the area of modern Belgium included the Duchy of Brabant, the County of Flanders, the Prince-Bishopric of Liège and the Duchy of Luxembourg; smaller ones included the County of Hainaut, the Duchy of Limburg and the County of Namur,