The wars between Denmark and the German Confederation—the First Schleswig War (1848–1851) and the Second Schleswig War (February – October 1864)—and the Gastein Convention of 1864, led to Denmark's cession of the Duchies of Schleswig and Holstein to Prussian administration and Lauenburg to Austrian administration. Along with all of Schleswig-Holstein, Altona became part of the Kingdom of Prussia in 1867.