Greenlee D. Letcher was the youngest son of John Letcher, governor of Virginia (1860-1864) and Mary Susan Holt Letcher. Greenlee graduated from the Virginia Military Institute in 1886 and Washington and Lee University Law School in 1888. He represented Rockbridge County as a delegate in the Virginia General Assembly between 1889 - 1893. He served as a Captain of Field Artillery in the 29th Division of the U.S. Army in the First World War, though the battery did not see combat before the November 11, 1918 armistice ended the war. Letcher had a longtime law practice in Lexington, Va. He married Katherine Paul of Rockingham County, Virginia and had three children.