Sylvia Pankhurst grew increasingly unhappy about the Women's Social and Political Union (WSPU) decision to abandon its earlier commitment to socialism. She also rejected the WSPU attempts to gain middle class support by arguing in favour of a limited franchise. Pankhurst made the final break with the WSPU when the movement adopted a policy of widespread arson. Sylvia now concentrated her efforts on helping the Labour Party build up its support in London.
In 1913, Sylvia Pankhurst, with the help of Keir Hardie, Julia Scurr, Mary Phillips, Millie Lansbury, Eveline Haverfield, Lilian Dove-Wilcox, Maud Joachim, Nellie Cressall and George Lansbury established the East London Federation of Suffragettes (ELF). An organisation that combined socialism with a demand for women's suffrage it worked closely with the Independent Labour Party. Pankhurst also began production of a weekly paper for working-class women called The Women's Dreadnought. As June Hannam has pointed out: "The ELF was successful in gaining support from working women and also from dock workers. The ELF organized suffrage demonstrations and its members carried out acts of militancy. Between February 1913 and August 1914 Sylvia was arrested eight times. After the passing of the Prisoners' Temporary Discharge for Ill Health Act of 1913 (known as the Cat and Mouse Act) she was frequently released for short periods to recuperate from hunger striking and was carried on a stretcher by supporters in the East End so that she could attend meetings and processions. When the police came to re-arrest her this usually led to fights with members of the community which encouraged Sylvia to organize a people's army to defend suffragettes and dock workers. She also drew on East End traditions by calling for rent strikes to support the demand for the vote."
The outbreak of the First World War caused further conflict between Sylvia Pankhurst and the WSPU. Sylvia was a pacifist and disagreed with the WSPU's strong support for the war. Sylvia Pankhurst joined with Charlotte Despard to form the Women's Peace Army, an organisation that demanded a negotiated peace.
In March 1916 Sylvia Pankhurst renamed the East London Federation of Suffragettes, the Workers' Suffrage Federation (WSF). The newspaper was renamed the Workers' Dreadnought and continued to campaign against the war and gave strong support to organizations such as the Non-Conscription Fellowship. The newspaper also published the famous anti-war statement in July, 1917, by Siegfried Sassoon.
Sylvia Pankhurst was a supporter of the Russian Revolution in 1917 and visited the country where she met Lenin and ended up arguing with him over the issue of censorship. The government disliked Sylvia's pro-Communist articles in her newspaper and she was imprisoned for five months for sedition. After she was released from prison Pankhurst renamed her organization the Workers' Socialist Federation.
On 31st July, 1920, a group of revolutionary socialists attended a meeting at the Cannon Street Hotel in London. The men and women were members of various political groups including the British Socialist Party (BSP), the Socialist Labour Party (SLP), Prohibition and Reform Party (PRP) and the Workers' Socialist Federation (WSF).
It was agreed to form the Communist Party of Great Britain (CPGB). Early members included Tom Bell, Willie Paul, Arthur McManus, Harry Pollitt, Rajani Palme Dutt, Helen Crawfurd, A. J. Cook, Albert Inkpin, J. T. Murphy, Arthur Horner, John R. Campbell, Bob Stewart and Robin Page Arnot. McManus was elected as the party's first chairman and Bell and Pollitt became the party's first full-time workers. It later emerged that Lenin had provided at least £55,000 (over £1 million in today's money) to help fund the CPGB.
Sylvia Pankhurst considered the CPGB to be too right-wing and was completely opposed to the idea of it being affiliated to the Labour Party. She was eventually expelled from the CPGB for refusing to allow the Dreadnought from being controlled by the party executive.
The Workers' Socialist Federation was closed down in June 1924.