Recent scholarship emphasizes the persistence of radical republicanism in Chartism and beyond. This republicanism focused on political ills not social ones and sought to elevate the people not the working-class. To recognize its persistence is, however, to raise a transition problem: how did the socialism of the twentieth century emerge out of, or even supplant, the republican tradition? We can answer this question by looking at the Social Democratic Federation (SDF). In the 1880s, the members of the SDF, including Tory radicals such as Hyndman, popular radicals such as the Murray brothers, and positivists such as Bax, typically moved from a radical republicanism to a form of Anglo-Marxism. Although they broke with republicanism, its legacy can be found their commitment to a strong democratic program, which has since characterized much of the radical left. The later history of the SDF finds them defending this program against the forms of socialism--rooted in romanticism and liberal radicalism rather than republicanism--found in the Socialist League, the Fabian Society, and eventually the Labour Party.