In 1867, the North German Confederation was created as a federation (federally organised state) of the North German and Central German states under the permanent presidency of Prussia. William assumed the "Bundespräsidium", the presidium of the Confederation; the post was a hereditary office of the Prussian crown. Not "expressis verbis", but in function he was the head of state. Bismarck intentionally avoided a title such as "Präsident" as it sounded too republican. William became also the constitutional "Bundesfeldherr", the commander of all federal armed forces. Via treaties with the South German states, he also became commander of their armies in times of war. In 1870, during the Franco-Prussian War, William was in command of all the German forces at the crucial Battle of Sedan.