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
Revolution of 1848 in Luxembourg powers. After being annexed by the French in the Napoleonic Wars, Luxembourg was elevated to a Grand Duchy and awarded to the Dutch King by the Congress of Vienna in 1815. While it was supposed to be ruled by him in personal union, rather than as part of his kingdom, the King-Grand Duke William I treated it merely as a province of the Netherlands. (At the time, modern Belgium was part of the Netherlands, so Luxembourg was not separated from Dutch territory.) The Grand Duchy would also be part of the German Confederation (the successor to the Holy Roman Empire),