Born in Westminster, Stenning left school aged thirteen and a half.
[1] He joined the Social Democratic Federation in 1906, aged sixteen,[2] and was a peace campaigner during World War I.
[1] He later joined the ILP, working at the ILP bakery in Bermondsey after the war.
[3] In 1920 he criticised Bolshevism as 'a recrudescence of Blanquism' in an article for Labour Leader,[4] and published a translation of Karl Kautsky's The Dictatorship of the Proletariat.
[5] He also worked as a publisher's reader, and from 1925 ran a law stationers' business in the City of London.