All hope for Waterloo’s labor activists was not lost, however. Organizers for the International Association of Machinists came to town in the summer of 1919, and their presence led to the most massive strike in the city up to that time. On July 28, 450 machinists at the Iowa Dairy Separator Company walked off the job. Their demands included an eight-hour workday and equal pay for women, although very few women were employed as machinists. The main issue, however, was the right of the recently-formed union to bargain collectively. Up to that point, employees were usually forced to sign "yellow-dog" contracts, under which they promised not to join a union and, therefore, were forced to negotiate with management on an individual basis.
Over the next three days workers at other companies went on strike. Tensions really began to rise on July 31, when 900 machinists at the Deere plant walked out. Machinists’ Local 314 official C.H. Milnes suggested that if the workers and Deere management failed to resolve the dispute quickly, Waterloo might witness a general strike like that which had occurred in Seattle in February of that year.
Outsiders were taking considerable interest in developments in Waterloo. The International Association of Machinists representative, A.G. Abbey, was at the center of the action and was blamed by business leaders for instigating worker instability. Reflecting the anti-socialist hysteria rampant during the Red Scare of 1919, one member of management declared that Abbey was a known associate of Minneapolis Socialists. The Department of Labor also took an interest and sent H.D. Rogers to mediate the dispute. All together, more than 2,000 workers at 13 factories were involved in the strike.
It was only a matter of time before mild violence became a feature of the dispute. Workers trying to go to work at the tractor plant were physically accosted, not only at the picket lines but on the streets of Waterloo. In an effort to prevent this, the two main companies involved, Iowa Dairy Separator and John Deere, sought refuge in the legal system and were granted injunctions against striker interference with those attempting to reach their jobs. On August 18, the Black Hawk County Sheriff selected 1,000 new deputies to quell the disturbances.
At the end of August the strikers asked Iowa governor W.N. Harding to intervene by appointing a board of arbitration to study the dispute. Deere and Company refused to participate, arguing that the majority of workers at their plant were satisfied with current conditions and that outsiders and radicals were responsible for creating trouble. An arbitration board was formed anyway and found that the strikers’ complaints were legitimate. This judgment was ignored by employers, however, and because the workers could not hold out forever, the strike failed to achieve its goals. By the first part of October, more than 100 men returned to the tractor plant; workers returned at a steady rate throughout October and early November until by the second week of November 366 workers were back on the job.
1919 was a year of labor unrest throughout the country. The cost of living rose dramatically following the war, and workers in all kinds of industries felt that while their bosses continued to get richer, they were being left behind. The same week which saw the beginning of the Waterloo strike also saw strikes of streetcar workers in Davenport, dock workers in Michigan and Wisconsin, and railroad workers in Chicago and throughout the southeastern states. Iowa coal miners also demanded a pay increase and threatened to strike. A.G. Abbey defended himself against charges of outside agitation by arguing that "all action taken in these strikes [in Waterloo] is being taken by the workmen themselves . . . Waterloo was ripe for a general upheaval in factory conditions . . . "
Although the Waterloo strike of 1919 failed to achieve its goals directly, it was only a matter of time before the mood of the country allowed for greater respect for American labor. The Progressive movement of 1900-1920 had already brought changes in child-labor laws, the status of women workers, and the number of hours employees could be required to work. Although these changes were not spread uniformly through all industries, they represented a desire on the part of citizens to improve working conditions. The late 1910s and 1920s would be hard times on many in the labor movement, as it was associated with radicalism and Communism, but labor unions were destined to become a permanent and powerful fixture on the American landscape. In Waterloo, although unionization got off to an extremely slow start in the first two decades of the century, the growth of Deere and Company and the Rath Packing Company in ensuing decades meant that unions would also become an important feature in the life of Black Hawk County.
