The BSP had meanwhile formed the Communist Party of Great Britain (CPGB). Lenin called on other communists to join the new party, and the CP(BSTI) was one of the groups covered in his work "". Although "Workers Dreadnaught" was openly critical of this pamphlet, Pankhurst attended the Second Congress of the Comintern, where Lenin personally persuaded Sylvia that her objections were less important than unity, and that it would be possible to maintain an anti-Parliamentary opposition within the CPGB. Pankhurst called a conference, inviting the English Shop Stewards' and Workers' Committee Movement, the Communist Labour Party, the Scottish Workers' Committee and the Glasgow Communist Group. She was arrested in September, but with the support of Willie Gallacher, all the groups at the conference bar Guy Aldred's Glasgow Communist Group agreed to merge with the Communist Party of Great Britain in January 1921.