Accordingto his WWI draft registration card, Arthur Marsden Barnum was born on January 26, 1892, in Utica, New York. He was a son of Frederick E. and Nettie Marsden Barnum. He and his wife had four children: Lois Mildred, Donald A. born about 1923, Alan R. born about 1927, and Ted M. born after 1930. (1930 Census).
From the Utica Daily Press, Monday,November 29, 1948: Arthur M. Barnum, 56, veteran of 10 World War I battles, died at his home Saturday (November 27, 1948) night after a three week illness. Born in Utica, NY, January 26, 1892, a son of Nettie Marsden Barnum and the late Fred Barnum, he attended local schools. He married Gertrude McMahon in St. Francis de Sales Church, January 18, 1918. Employed as a civil engineer by the New York State Highway Department for the past 35 years, Mr. Barnum participated in 10 battles in the smashing of the Hindenburg Line. Besides his wife and mother, he is survived by a daughter, Mrs. Harold (Lois) Luther, three sons, Donald, Alan and Ted all of Utica; a sister, Mrs. Mildred Board, Utica; five brothers, Charles and Roy of Utica; Edwin, Lyons Falls; John, Ilion; and Robert, Montgomery, three grandchildren and several nieces and nephews.