The memoirs

"Otto Eduard Leopold, Prince of Bismarck, Duke of Lauenburg (1 April 1815 ? 30 July 1898), simply known as Otto von Bismarck, was a conservative German statesman who dominated European affairs from the 1860s to his dismissal in 1890 by Emperor Wilhelm II. In 1871, after a series of short victorious wars, he unified most of the German states (whilst excluding some, most notably Austria) into a powerful German Empire under Prussian leadership. This created a balance of power that preserved peace in Europe from 1871 until 1914."--Wikipedia.