When Harold Bridge Atherstone was born on 18 March 1879, in San Francisco, San Francisco, California, United States, his father, Thomas Shelton Atherstone, was 36 and his mother, Emma Bithia Bridge, was 32. He married Amarcia Lillian Erwin on 17 August 1904, in Sonora, Tuolumne, California, United States. They were the parents of at least 5 sons and 1 daughter. He lived in Sausalito, Marin, California, United States in 1910 and Turlock Judicial Township, Stanislaus, California, United States in 1940. He died on 5 March 1956, in Turlock, Stanislaus, California, United States, at the age of 76, and was buried in French Camp, San Joaquin, California, United States.