The Gilded Age, which spanned roughly from the late 1870s to the early 1900s, was a time of rapid industrialization, economic growth, and prosperity for the wealthy. It was also a time of exploitation and extreme poverty for workers.
Jeremy Brecher's account of the growth of the Knights of Labor union in the US, the agitation for a maximum 8-hour working day and the Chicago Haymarket events of 1886.