A map showing the formation of the German Empire between 1806 and 1871. This map shows the territory of Prussia after the war with Napoleon in 1806, the territory added to Prussia by the Congress of Vienna in 1815, Schleswig and Holstein taken from Denmark in 1864, Hanover annexed after the War of 1866, the German states which joined Prussia to make the German Empire, and Alsace and Lorraine territories taken from France in 1871.