Although many conditions can lead to labor unrest, the most common are poor and dangerous working conditions, unfair pay for the labor provided and income inequality among workers. American labor unrest in the late-19th and early-20th century came from a shift in socioeconomic status among laborers.
In the United States, just prior to the Civil war, about four out of five free adult men owned property, and in general, farmers and craftsmen owned the property on which they worked. Post-civil war times, however, saw the expansion of factories, and the formation of a rift between management and labor. Immigration brought workers willing to labor for lower wages, and debates over fair wages and hours raised questions of slavery and feudalism.
Economic booms and busts also contributed to labor unrest. One such incident, called the Great Railroad Strike of 1877, was brought on by these conditions. Between 1866 and 1873, nearly 35,000 miles of railroad track was laid in the United States. During this time, speculators fed large amounts of money to the industry, which led to an over-expansion. The strike, which stopped railroads from running in Maryland, Pennsylvania, Illinois and Missouri, resulted from the collapse of a major firm in the industry, precluding a 45 percent overall reduction in wages and a severe reduction in the workforce.