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Irc History: The Ludlow Massacre
A good explanation of the Ludlow Massacre in the coalfields of Colorado and what led up to it. In addition, there is an interesting description of how this violent reaction to a strike by miners affected John D. Rockefeller, Jr., one of...
PBS
Pbs: American Experience: The Rockefellers: The Ludlow Massacre
This American Experience film about the Rockefellers includes this accounting of the Ludlow Massacre in Colorado and John D. Rockefeller, Jr.'s role in the business decisions that had a role in fomenting it.