Workers marching for the Eight-hour day in Milwaukee, Wisconsin were shot at by Wisconsin National Guardsmen in what became known as the Bay View Massacre.

The eight-hour day movement was a social movement that appeared in various countries to regulate the length of a working day. The goal was preventing excesses and abuses of working time.

Milwaukee is the most populous city in the U.S. state of Wisconsin. Located on the western shore of Lake Michigan, it is the 31st-most populous city in the United States and fifth-most populous city in the Midwest with a population of 577,222 at the 2020 census, while the Milwaukee metropolitan area with over 1.57 million residents is the 40th-largest metropolitan area in the nation. It is the county seat of Milwaukee County.

Wisconsin is a state in the Upper Midwest and Great Lakes regions of the United States. It borders Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. With a population of about 6 million and an area of about 65,500 square miles, Wisconsin is the 20th-largest state by population and the 23rd-largest by area. It has 72 counties. The state's most populous city is Milwaukee. Its capital and second-most populous city is Madison; other urban areas include Green Bay and the Fox Cities.

The Wisconsin National Guard consists of the Wisconsin Army National Guard and the Wisconsin Air National Guard. It is a part of the Government of Wisconsin under the control of the Wisconsin Department of Military Affairs. The Wisconsin National Guard dates back to 1848 when it was commissioned by the State as the "Wisconsin State Militia". In 1879, the organization's name was changed to its current title.