17. Soule wrote letters describing the massacre to family and friends, including Whitman
Following the Sand Creek event, Chivington called the attack a battle, and the Colorado Volunteers were lauded as heroes in Denver and the regions where the Cheyenne depredations had occurred (and continued to occur). In a letter to Edward Wynkoop, known as Ned to friends, Silas wrote, “I tell you Ned, it was hard to see little children on their knees have their brains beat out by men professing to be civilized”. Soule wrote in a similar vein to Whitman, as well as others, and the Army, under pressure from the prominent abolitionists, opened an investigation into the event at the time known as the Battle of Sand Creek.
Chivington retired from the Army in January, 1865, just over one month following the massacre, and in doing so removed himself from the jurisdiction of a military court martial. The investigation was held in the form of a Military Court of Inquiry in Denver. The city and public opinion were sharply divided, with some continuing to praise Chivington and the Colorado Volunteers as heroes, and those who condemned the Sand Creek action as “Fort Lyon Indian lovers”. Threats against Soule, and others who testified against Chivington were common.