This collection showcases more than 3,800 images of original manuscripts, broadsides, photographs, prints and artifacts relating to the Haymarket Affair. The violent confrontation between Chicago police and labor protesters in 1886 proved to be a pivotal setback in the struggle for American workers' rights. These materials pertain to: the May 4, 1886 meeting and bombing; to the trial, conviction and subsequent appeals of those accused of inciting the bombing; and to the execution of four of the convicted and the later pardon of the remaining defendants. Of special interest and significance are the two dozen images of three-dimensional artifacts, including contemporary Chicago Police Department paraphernalia, labor banners, and an unexploded bomb casing given to juror J. H. Brayton by Chicago Police Captain Michael Schaack. The cornerstone is the presentation, as images and searchable text, of the transcript of the 3,200 pages of proceedings from the murder trial of State of Illinois v. August Spies, et al.