In 1892, he was a founder of the Belfast Socialist Society, within which he promoted Irish Home Rule.
[1] In 1895, he moved to Barrow-in-Furness, and within three years, he became the Amalgamated Society of Engineers (ASE) district secretary.
[3] Stephenson was also active in the Independent Labour Party, which selected him as its candidate for the 1908 Newcastle-upon-Tyne by-election.
However, this was in conflict with the electoral alliance that existed locally between the Liberal and Labour parties, and the National Executive persuaded Stephenson to withdraw.
[4] At the January 1910 general election, he stood for Labour in Birmingham East, initially being promised the support of the businessman Dudley Docker, but this was later withdrawn, and Stephenson lost the election.