What caused textile mill workers in the south to go on strike in 1934?

The answer is: The textile workers' strike of 1934 was the largest strike in the labor history of the United States. As one union organizer said, textile workers in the South saw the NIRA as something that "God has sent to them." In what proved to be a dry run of the larger strike to follow, cotton mill workers in SouthCarolina's Horse Creek

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Companies had continued to lower the wages, and increased their working hours.