Hermann Oncken (12 November 1869, Oldenburg, Germany – 28 December 1945, Göttingen, Germany) was a German historian and political writer. He was one of the most notable historians of pre-Nazi Germany.
He lectured at the universities of Chicago (1905), Giessen (1906), Heidelberg (1907-1923), Munich (1923-1928), and Berlin (1928-1935). In 1935 he was forced to retire by the Nazi regime, which he opposed.
He specialized in the 19th century, history of historical thought, history of political thought.
Notable students: