Who were the settlers of the Boulder Valley?

Who were the Euro-American people who settled in the Boulder Valley in the mid01800s? What were their ethnicities, relitions, genders, social class? Where did they come from? What were their attitudes about Native peoples, Manifest Destiny, the treaties (and violating them), land ownership? How did they relate to Chief Nawath's band of Arapaho who lived in the Boulder Valley? What drove them to join the US Cavalry and commit the Sand Creek Massacre? After the massacre, what did they say or write about it and its aftermath? How did they envisioin the future population of Boulder?