The year 1886 was destined to be a crucial one in the history of the American labor movement. The eight-hour crusade, the numerous strikes, the Haymarket bomb, the entrance of workingmen into the political arena at the state and national levels, and the mushroom growth of labor organizations all contributed to the agitation and excitement of the year. Yet the importance of these events was overshadowed by a development that was to have such far-reaching implications that it would determine the future of the labor movement for the succeeding half century. That development was the declaration of war by the trade unions against the reform unionism of the Knights of Labour.