William was the son of Johnathan W. Yerian and Alice Rupert. He married about 1904 to Myrtle Hum. They appear in the 1910 census of Alliance City, Stark County, Ohio. He was a city postman. In 1930 they were still in Alliance. He was a postal clerk.
Children of William and Myrtle: Mary M. Yerian (ca.1905-unk) Howard M. Yerian (1908-1972)