Rudolf Doehn (2 February 1821, Hinrichshagen – 9 April 1895, Dresden) was a German writer and journalist. He belonged to the Forty-Eighters who participated in the American Civil War as volunteers in the Union Army. Here he became also known as Randolph Doehn.
Rudolf Doehn studied philosophy at the University of Halle-Wittenberg, wrote his Dissertation de speculativo logices Platonicae principio on Plato at the University of Greifswald in 1845, and continued his studies of jurisprudence in Berlin and at the . After the defeat of the revolutions of 1848 in the German states he emigrated to the United States in 1854. Doehn settled in St. Louis, worked as a teacher for the freethoughts, and married Francisca Martins in 1858.
In 1860 Doehn was elected to the Missouri House of Representatives. He belonged to the German volunteers who helped prevent Confederate forces from seizing the government arsenal in St. Louis during the Camp Jackson Affair. His wife supported him and called in the Anzeiger des Westens for supporting John C. Frémont and Franz Sigel. Doehn was a member of the Missouri General Emancipation Society, founded by Benjamin Gratz Brown und Charles D. Drake, who demanded even more consequent measures against slavery as foreseen by Abraham Lincoln in his Emancipation Proclamation of 1862, which excluded border states like Missouri.