Portal:Chicago/Selected landmark/11

The Haymarket affair (also known as the Haymarket riot or Haymarket massacre) on Tuesday 4 May 1886 in Chicago, began as a rally which became violent and was followed later by internationally publicized legal proceedings. An unknown person threw a bomb at police as they marched to disperse a public meeting in support of striking workers. The bomb blast and ensuing gunfire resulted in the deaths of seven police officers and an unknown number of civilians. Eight anarchists were tried for murder. Four were put to death, and one committed suicide in prison. The Haymarket affair is generally considered to have been an important influence on the origin of international May Day observances for workers. The causes of the incident are still controversial, although deeply polarized attitudes separating business and working class people in late 19th century Chicago are generally acknowledged as having precipitated the tragedy and its aftermath. The site of the incident was designated as a Chicago Landmark on 25 March 1992. The Haymarket Martyrs' Monument in nearby Forest Park was listed on the National Register of Historic Places and as a National Historic Landmark on 18 February 1997.