On the morning of November 29, 1864, Colorado state cavalry under the command of Col. John Chivington attacked a peaceful encampment of mostly Cheyenne Indians along the Sand Creek in Colorado, slaughtering perhaps as many as 160 people, mostly women and children. It was one of the most egregious atrocities of the Indian Wars. Even with the country embroiled in a Civil War, the gravity of the situation can be gauged by the fact that within six weeks of the killings, a Joint Committee of Congress conducted a public hearing. Congress vilified Chivington summarizing his cowardly and racist attack in their published report: “Wearing the uniform of the United States, which should be the emblem of justice and humanity ...he deliberately planned and executed a foul and dastardly massacre.” This facsimile of this important report contains annotations made by a reader at the time as well as the typescript testimony of the African-American pioneer, James P. Beckwourth, in which he recounts the atrocity. This edition is introduced by Bill Yenne who places the Sand Creek Massacre in context and provided biographical information about the main persons involved.