During the suffrage campaign she not only braved the horrors of hunger striking and forcible feeding, but also founded and built a remarkable women’s organisation in the East End of London  - the East London Federation of Suffragettes (ELFS). She attempted to forge a link between the women’s movement and the labour movement and in doing so was unafraid to tackle the vexed question of the relationship between class and gender, and between feminism and socialism. It was this question above all others which led to a major and irreversible split within one of the most important of the women's suffrage organisations, the Women's Social and Political Union (WSPU, commonly know as the Suffragettes, founded in 1903). This split mirrored the ideological rift with her mother, Emmeline, and elder sister, Christabel, the founders and prime movers of the WSPU.

The WSPU abandoned its early links with the labour movement in 1907 and, in 1914, with the outbreak of the First World War, it abandoned the suffrage campaign itself. Emmeline and Christabel Pankhurst ardently supported the war effort and urged all women to do the same. Sylvia did not take their advice and was expelled by her mother and sister for her disobedience.

The East London Federation of Suffragettes, was composed of working class women who campaigned for the vote and for social change in the period 1912-1920. They maintained the suffrage battle during the war years as well as establishing many practical projects in the East End to relieve distress. The ELFS weekly paper, The Women’s Dreadnought (later, The Worker’s Dreadnought), owned and edited by Sylvia, had a high circulation and was influential outside London.

The ELFS moved steadily to the left during the war: it supported the Irish struggle for independence, the Russian Revolution and briefly played a role in the formation of the Communist Party of Great Britain.

Sylvia Pankhurst was a pioneer in other ways. Apart from the fact that during her long and active life she founded and edited four newspapers, wrote and published 22 books and pamphlets not to mention literally countless articles, she was a founder and tireless activist in a variety of women’s, labour movement and international solidarity organisations. She was a deeply committed anti-racist and anti-fascist and involved for over 30 years in campaigning on such issues which included the cause of Ethiopia – the country which became her home for the last four years of her life and in which she was buried.

The independence of Ethiopia - “the black man’s last citadel” - was ended when it was invaded and conquered by Fascist Italy in 1935. Sylvia, almost alone among the white left, rallied to its cause and launched in 1936 the first edition of the New Times and Ethiopia News, a weekly paper which remained in circulation for 20 years and which, at its height sold 40,000 copies weekly. This included an extensive circulation throughout West Africa and the West Indies.