Luxembourg an independent state under the personal possession of William I of the Netherlands with a Prussian garrison to guard the city against another invasion from France. In 1839, following the turmoil of the Belgian Revolution, the purely Oil-speaking part of Luxembourg was ceded to Belgium and the Luxembourgish-speaking part (except the Arelerland, the area around Arlon) became what is the present state of Luxembourg. Luxembourg is a founding member of the European Union, OECD, United Nations, NATO, and Benelux. The city of Luxembourg, which is the country's capital and largest city, is the seat of several institutions and agencies of
Belgium–Luxembourg Economic Union some relevance in being able to decide more precise measures than these organisations. International trade statistics were available for BLEU only as a combined entity until 1999, when European Community rules required split information. Compared with the Zollverein, the UEBL had several advantages for Luxembourg. Belgium was only allowed to alter its customs tariffs or conclude trade treaties after consultation with the Luxembourgish government, whereas before 1918 Luxembourg had to go along with German decisions. Similarly, only Luxembourgish customs agents would operate in Luxembourg, while under the Zollverein Prussian officials had operated in Luxembourg. The functioning of the UEBL was