Richard Ratcliffe Farr was born on November 30, 1845, in Fairfax County and was the son of Richard Ratcliffe Farr, who died about ten weeks before he was born, and Margaret Conn Willcoxon Farr, who reared him and his elder brother. During the Civil War, he and his mother lived as refugees in Washington County after the Second Battle of Manassas in August 1862. On November 2, 1863, he enlisted as a private in Company B of the 43rd Virginia Cavalry Regiment, under the command of John Singleton Mosby. One year later Farr was severely wounded in the thigh, but he recovered and served until paroled in Winchester in April 1865.