I think it was called a citizen's army because when citizens came together to form a 'army' the normal army, and other countries, referred to them as a 'citizen's army'
Hope this helps! :)
Answer:
C
Explanation:
More than 230 Native Americans were massacred, including some 150 women, children, and elderly. Thirteen Cheyenne chiefs and one Arapaho chief were killed. Chivington was at first acclaimed for his “victory,” but he was subsequently discredited when it became clear that he had perpetrated a massacre.