Othniel Charles Marsh (1831–1899) was an American paleontologist who made numerous contributions to the field of paleontology. In addition to his contributions to the evolutionary history of the horse, he discovered and named numerous dinosaurs during the “Bone Wars” of the late 1800s. In 1866, he helped establish, with the financial backing of his uncle George Peabody, the Peabody Museum of Natural History at Yale University; he was also a professor at Yale.

In 1882, Marsh published the first dinosaur classification, which formed the foundation for the modern dinosaur classification. In the same year, Marsh was appointed as an official vertebrate paleontologist of the United States Geological Survey.