Major archival collections pertaining to the strike and the massacre exist in Colorado, Pennsylvania, and New York. The Denver Public Library’s Western History Department holds extensive collections related to these events, including the papers of union leaders Edward Doyle and John Lawson, the papers of National Guard officer Philip Van Cise, and the proceedings of the Colorado National Guard court-martial that followed the massacre.
The Colorado Historical Society also has extensive collections related to the strike. In 2003 the Colorado Fuel and Iron Company turned its papers, including those relating to the period of the strike, over to the Bessemer Museum in Pueblo, Colorado. In 1994 the United Mine Workers of America transferred its archives from Virginia to the Historical Collections and Labor Archives at Pennsylvania State University in State College.
At some point when the archives were in storage in Virginia, Unearthing Class War boxes related to the 1913–1914 Colorado strike and the Ludlow Massacre disappeared. Some materials pertaining to the strike can be found in correspondence files for District 15 and the union’s executive committee. John D. Rockefeller. -from Archaeology of Class War