Following the Napoleonic wars and the dissolution of the Holy Roman Empire the North German Confederation, led by Prussia, was combined with the southern states of Baden, Württemberg, Bavaria and Hesse and the formerly French newly annexed Alsace-Lorraine to form the German Empire in 1871.
Britain ceded Heligoland to Germany in 1890 in accordance with the terms of the Heligoland-Zanzibar Treaty.