Black Kettle’s band of Southern Cheyenne, approximately 500 to 600 people, were camped in a bend of Sand Creek.

With them were a smaller number of Southern Arapaho under the chief Left Hand.

The camp was in a location that had been designated by the military.

The people there understood themselves to be under military protection.

Colonel Chivington arrived at Fort Lyon with his command on the evening of November 28.

He had marched through the night to prevent news of his approach from reaching the camp.

The officers at Fort Lyon objected to the proposed attack — they told Chivington that the camp was friendly, that the people there had placed themselves under military protection, and that attacking them would be a violation of the assurances they had been given.