In 1830, Belgium seceded from the Kingdom, a step that was recognised by the Netherlands only in 1839 in the Treaty of London.  At that point, Luxembourg became a fully independent country in a personal union with the Netherlands. Luxembourg also lost more than half of its territory to Belgium.  To compensate the German Confederation for that loss, the remainder of the Dutch province of Limburg received the same status that Luxembourg had enjoyed before, as a Dutch province that at the same time formed a Duchy of the German Confederation.  That status was reversed when the German Confederation ceased to exist in 1867 (briefly replaced by the Prussian-led North German Confederation until the proclamation of a unified German Empire in 1871), with Limburg reverting to its status as an ordinary Dutch province.