Heinz, Frederik Ole, 1974-

The Railroad strike of 1877, often referred to by historians as the great upheaval, was a massive revolt against the growing concentration of wealth and economic disruption following rapid technological change. Nowhere was the union movement stronger than in Pittsburgh. In a confrontation on July 21, the militia opened fire killing about twenty people. A battle followed and the rail yards were looted and burned. Federal troops occupied the city on July 27th and the strike and union collapsed.

From the description of Start of the Pittsburgh Riots of 1877 : my experience during July 21, 22 and 23 / Fred J. Heinz h[mansucript]. (Historical Society of W Pennsylvania). WorldCat record id: 55490277