Hatfield was born in Logan County, West Virginia on September 15, 1875. He graduated from Franklin College in New Athens, Ohio. He later obtained medical degrees from what is now known as the University of Louisville and later from New York University.
He was appointed as surgeon for the Norfolk and Western Railway (1895 - 1913) and surgeon in chief of State Hospital #1 in Welch, West Virginia (1899 - 1913). He entered local politics first as commissioner of district roads of McDowell County (1900 - 1905), eventually becoming member of the State senate (1908 - 1912), and serving as president of the senate in 1911.
He was elected as Governor of West Virginia in 1912. His term was marked by his staunch support of labor unions and worker's rights. At the time, West Virginia governors could not serve more than one term in office, and so following his term in 1917, he entered the United States Army as a Major in the Medical Corps, serving as chief of the Surgical Service at Base Hospital No. 36 in Detroit, Michigan.
He was discharged in 1919 and returned to West Virginia. In 1928, he was elected as a Republican representative of the Senate and served from March 4, 1929 to January 3, 1935. He was defeated in a bid for reelection in 1934.
He then settled in Huntington, West Virginia and established a private medical practice, where he worked until his death in 1962.