Ludlow Massacre: April 20, 1914 - one of deadliest attacks on striking workers in U.S. history. The governor of Colorado ask for federal troops to restore order, and Woodrow Wilson complied. This accomplished, the strike petered out. Congressional committees came in and took thousands of pages of testimony. The union had not won recognition. Sixty-six men, women, and children had been killed. Not one militiaman or mine guard had been indicted for crime.