William Brunton was born in Sheffield, England, in the mid-19th century, and had four siblings: Mary, Eliza, John, and Riley. He worked as an errand boy and in a mill during his youth, and graduated from the Unitarian Home Missionary College in Manchester, England, in 1869. In December 1871, he emigrated to the United States, where he led several congregations in New York and Massachusetts before attending Harvard Divinity School. After his graduation in 1879, he resided in Boston and in Fairhaven, Massachusetts. He retired in February 1905, and died on March 10, 1906. He and his wife, Elma Amelia Summer ("Nellie") of Braintree, Vermont, married in October 1872, and had one son, Herbert.
Herbert Rogers Brunton was born in Vermont on March 18, 1876, and lived with his family in Boston, Massachusetts. He graduated from Boston Dental College (now part of Tufts University) in 1897 and practiced dentistry in Malden, Massachusetts, where he lived with his wife Ethel and their two children, Robert and Barbara.