Alfred Mason, the son of Rosetta and George Miles Mason, was born in Southampton in 1892. His father was an astronomer and an optician. On other documents he is recorded as being an artist and maker of lanteen slides.
In 1908 Mason started an apprenticeship with Mr Martin, a chemist of 118 High Street, Southampton. At the age of 20 he began work at the Analytical Department of Guy's Hospital in London.
On 29th May 1915, Mason married Winnie Wheeldon. The couple moved to Southampton, where Mason worked as a chemist for Phillip Eley of Shirley Road. He was also employed as a lecturer at Hartley University. Winnie became a teacher at the Foundry Lane Council School.
Winnie Wheeldon was active in left-wing politics. She was a socialist and a member of the Socialist Labour Party (SLP) . She was also active in the Women's Social and Political Union (WSPU). Her mother, Alice Wheeldon and her sister and brother, Hettie Wheeldon and William Wheeldon, shared her political views. Alfred Mason also appears to have been influenced in these matters by his wife.
The outbreak of the First World War caused conflict between Winnie Mason and the WSPU. Winnie was a pacifist and disagreed with the WSPU's strong support for the war. Sylvia Pankhurst and Charlotte Despard established the Women's Peace Army, an organisation that demanded a negotiated peace. Winnie, Alice Wheeldon and Hettie Wheeldon, all joined this new political group. Other members included Helena Swanwick and Olive Schreiner.