German historian and political writer whose advocacy of power politics was influential at home and contributed to distrust of Germany abroad.

The son of a Saxon general, Treitschke studied at Bonn and Leipzig. He taught history and politics at the University of Leipzig (1859) and went on to teach at Freiburg (1863), Kiel (1866), Heidelberg (1867), and Berlin (1874). From 1866 to 1889 he edited the Preussische Jahrbücher (“Prussian Yearbooks”), a journal influential in his field. From 1871 to 1884 he was a member of the Reichstag, first as a National Liberal and then as a moderate conservative, but as a public figure he was handicapped by almost total deafness.

Treitschke was a proponent of authoritarian power politics and a vociferous herald of the unity of Germany through Prussian might. Treitschke believed that the state should be the centre of the lives of its citizens and that it should be headed by authoritarian rulers without the check of a parliament. He held that Germany was the true heir of the Holy Roman Empire; thus he pressed for its rise to the status of a great imperialist power. He disparaged western European liberalism and took an equally skeptical view of democracy in North America.

As a historian, Treitschke won great influence in Germany owing to his rhetorical gifts, his masterful literary style, and his colourful descriptions of political and cultural life. His writings contain many vehement and inaccurate political judgments, however, and his lack of objectivity stands in sharp contrast to the dispassionate learning of his great German contemporary, the historian Leopold von Ranke. After von Ranke's death in 1886, Treitschke was named official historiographer of Prussia. In 1895 he became editor of the Historische Zeitschrift (“Historical Journal”).

Treitschke's admiration for the early Hohenzollerns and his hatred of Prince von Metternich and the English are evident in his magnum opus, Deutsche Geschichte im 19. Jahrhundert, 5 vol. (1879–94; Treitschke's History of Germany in the Nineteenth Century), which covers the period from 1800 to 1848. Treitschke did not live to finish writing this work. His most important other works are the essays collected in Historische und politische Aufsätze, 4 vol. (1865–97; “Historical and Political Essays”), and his lectures on politics, collected in Politik, 2 vol. (1897–98).