Thomas Alfred Jackson was a founding member of the Socialist Party of Great Britain and later the Communist Party of Great Britain. He was a leading communist activist and newspaper editor and worked variously as a party functionary and a freelance lecturer.

The Social Democratic Federation (SDF) was established as Britain's first organised socialist political party by H. M. Hyndman, and had its first meeting on 7 June 1881. Those joining the SDF included William Morris, George Lansbury, James Connolly and Eleanor Marx. However, Friedrich Engels, Karl Marx's long-term collaborator, refused to support Hyndman's venture. Many of its early leading members had previously been active in the Manhood Suffrage League.