The only Grand-Duchy in the world, this small country has become one of the symbols of European integration. A former county that was ruled by the Netherlands under the Burgundians, then the Spanish, then the Austrians, it became part of the Kingdom of the Netherlands after the Congress of Vienna, from which it separated in 1890. Occupied by Germany in 1940 Luxembourg became one of the founder members of Benelux and then the European Union of which it is one of the main pillars. It hosts some of the European institutions and the Luxembourgers have undertaken some important offices at European level. It distinguishes itself in that it is particularly active in terms of development aid and is renowned for having established an extremely sophisticated social protection system. For a long time it played the role of mediator between France and Germany.