Prince Otto Eduard Leopold von Bismarck-Sch Ã nhausen Duke of Lauenburg ( 1 April 1815 â `` 30 July 1898 ) was a very well known aristocrat and statesman of the 19th century in Europe . Otto Eduard Leopold von Bismarck ( 1 April 1815 â `` 30 July 1898 ) was a German-Prussian statesman of the late 19th century , and a dominant figure in world affairs .