Edwin Warfield Beitzell, 79, a retired official of the Chesapeake & Potomac Telephone Co., the author of several books on St. Mary's County and southern Maryland, and a former member of the board of the Maryland Historical Trust, died Nov. 13 at St. Mary's Hospital in Leonardtown after a stroke.

Mr. Beitzell, who lived in Abell, Md., had served as the county historian of St. Mary's County since 1975. He was born in the county and moved to Washington in 1924 to attend Georgetown Unversity, where he graduated. He earned a degree in accounting at Benjamin Franklin University.

He joined the telephone company in 1926 and was supervisor of commercial engineering in 1967 when he retired and moved to Abell.

Mr. Beitzell's interest in southern Maryland history began in his boyhood, when he attended the St. Francis Xavier Catholic Church at Newtown Neck, the oldest Catholic church in English-speaking North America.

His books include "The Jesuit Missions of St. Mary's County," "Life on the Potomac River" and "Point Lookout Prison Camp for Confederates." From 1956 to 1981, he was the editor of Chronicles, the monthly publication of the St. Mary's County Historical Society. He was a member of the Maryland Bicentennial Commission, the St. Clement's Island/Potomac River Museum and the Sons of Confederate Veterans.

Mr. Beitzell received the John Carroll Award from the Georgetown University Alumni Association, the Father Andrew White S.J. Award from the Catholic Historical Society and an honorary doctorate from St. Mary's College.

Survivors include his wife, Josephine Kinney Beitzell of Abell; two children, Edwin W. Jr. of Los Angeles and Jean B. Quinnette of Arlington; a brother, Joe, of Upland, Calif.; a sister, Alice B. Husemann of Abell, and four grandchildren.