Henry McDonald Sedley (1881–1962) was an American actor. He caused the death of a fellow student while a freshman at Yale University in 1901, which may have been the reason for a young woman being banned by her grandmother from marrying him.Prior to achieving fame in silent film, he owned several racehorses and was a champion jockey. Born in New York in 1881, he attended St. Paul's school, Andover, and the Sheffield Scientific School at Yale University, though he did not complete a degree at Yale. He bought a 70 foot racing yacht from Alfred G. Vanderbilt, and was described as a bon vivant.When a freshman at Yale in 1901, he caused the death of a classmate, Edward F. Corrigan. He was expelled from Yale in the aftermath. In 1907 he reached a settlement for $300. About the same time, Oliver Barnes, a wealthy friend from Reno, Nevada, took Sedley under his wing and assisted his transition into the film industry. In 1912, he was in the news when a young woman's grandmother forbade her from marrying him.He was a stage actor for five years prior to transitioning to film in the late 1910s. Early in his film career he was known for playing villains. He was almost six feet tall. Having a slight build, he was not given to portrayals of physical conflict, but in at least one instance (in Straight is the Way, 1921) his fight scene was highlighted in a review. Early in his career he roomed with Adolphe Menjou, and the two shared their possessions and paychecks.His early film roles included The Daredevil, Thunderbolts of Fate, and The Kaiser's Bride.