Career
Born in Leeds, Megantic County, Quebec, the son of Thomas and Elizabeth (Kinnear) Cromwell, Cromwell was educated at public schools. He was mayor of Clinton, Quebec in 1902, a councilor in Eaton, Quebec in 1907, and a councilor in Cooksville, Quebec from 1909 to 1912. A farmer and manager, he was elected to the Canadian House of Commons for the electoral district of Compton in the 1911 federal election.
A Conservative, he did not run in 1917 but was defeated when he ran again in 1921.