Wellington D. Rankin (September 16, 1884 – June 4, 1966) was a Republican public official from the state of Montana. He was born Wellington Duncan Rankin on September 16, 1884 in Missoula, Montana, the son of John and Olive (née Pickering) Rankin. He grew up in a political family, with several of his relatives holding public office. He attended Harvard University, earning his bachelor's degree in 1905, and Harvard Law School, graduating in 1909. He was a Rhodes Scholar.