Otto, Prince of Bismarck, Count of Bismarck-Schönhausen, Duke of Lauenburg (German: Otto Fürst von Bismarck, Graf von Bismarck-Schönhausen, Herzog zu Lauenburg, pronounced [ˈɔtoː fɔn ˈbɪsmaʁk] (listen); 1 April 1815 – 30 July 1898), born Otto Eduard Leopold von Bismarck, was a conservative German statesman and diplomat. From his origins in the upper class of Junker landowners, Bismarck rose rapidly in Prussian politics, and from 1862 to 1890 he was the minister president and foreign minister of Prussia. Before his rise to the executive, he was the Prussian ambassador to Russia and France and served in both houses of the Prussian Parliament. He masterminded the unification of Germany in 1871 and served as the first Chancellor of the German Empire until 1890, in which capacity he dominated European affairs. He had served as the chancellor of the North German Confederation from 1867 to 1871, alongside his responsibilities in the Kingdom of Prussia. He cooperated with King Wilhelm I of Prussia to unify the various German states, a partnership that would last for the rest of Wilhelm's life. The King granted Bismarck the titles of Count of Bismarck-Schönhausen in 1865 and Prince of Bismarck in 1871. Bismarck provoked three short, decisive wars against Denmark, Austria, and France. Following the victory against Austria, he abolished the supranational German Confederation and instead formed the North German Confederation as the first German national state, aligning the smaller North German states behind Prussia, while excluding Austria. Receiving the support of the independent South German states in the Confederation's defeat of France, he formed the German Empire – which also excluded Austria – and united Germany.

With Prussian dominance accomplished by 1871, Bismarck skilfully used balance of power diplomacy to maintain Germany's position in a peaceful Europe. To historian Eric Hobsbawm, Bismarck "remained undisputed world champion at the game of multilateral diplomatic chess for almost twenty years after 1871, [and] devoted himself exclusively, and successfully, to maintaining peace between the powers".[2] However, the annexation of Alsace–Lorraine gave new fuel to French revanchism and Germanophobia.[3] Bismarck's diplomacy of Realpolitik and powerful rule at home gained him the nickname the Iron Chancellor. German unification and rapid economic growth were foundational to his foreign policy. He disliked colonialism but reluctantly built an overseas empire when it was demanded by both elite and mass opinion. Juggling a very complex interlocking series of conferences, negotiations and alliances, he used his diplomatic skills to maintain Germany's position.