Divisions in the Irish trade union movement opened up following the return of Jim Larkin from the USA in 1923. As a revolutionary socialist, Larkin had objections to the Free State settlement and the way the labour leadership both supported and accommodated itself within it. In addition to these political objections, however, Larkin also displayed a destructive egoism. Resenting the fact that he no longer controlled the union he had formed, the Irish Transport and General Workers’ Union (ITGWU), and that it was now controlled by William O’Brien, Larkin made a concerted effort to regain his leadership. Failure here led to the eventual establishment in 1924 of a new Larkinite union, the Workers’ Union of Ireland (WUI). Few members of the ITGWU outside Dublin joined the new union, but in the capital itself around two thirds did. Following the creation of the WUI a series of inter-union disputes broke out between O’Brienites and Larkinites, throwing into high relief not only the reformism and opportunism of the former but also the destructive egoism and vanity of the latter. The Inchicore railway strike of 1924 was one of the most significant—and bitter.