The strategic position of the Ardennes has made it a battleground for European powers for centuries. Much of the Ardennes formed part of the Duchy (since 1815, the Grand Duchy) of Luxembourg, a member state of the Holy Roman Empire, which changed hands numerous times between the powerful dynasties of Europe. In 1793 revolutionary France annexed the whole area, together with all other territories west of the Rhine river. In 1815, the Congress of Vienna, which dealt with the political aftermath of the Napoleonic Wars, restored the previous geographical situation, with most of the Ardennes becoming part of the Grand Duchy of Luxembourg. After the revolution of 1830, which resulted in the establishment of the Kingdom of Belgium, the political future of the Ardennes became a matter of much dispute between Belgium, Luxembourg, and the Netherlands, as well as involving the contemporary great powers of France, Prussia, and Great Britain. As a result, in 1839, the Grand Duchy of Luxembourg ceded the westernmost 63% of its territory (being also the main part of the Ardennes) to the new Kingdom of Belgium, which is now its Luxembourg Province.