Good to read this weaving of your family history with the colossal loss of life - the genocidal crimes of Europeans are marginalised when not completely erased. It makes it easier for them to bleat on about being an 'advanced civilisation ', at the same time as they were spread diseases by presenting the blanket of an infected person, as a gift. They knew exactly what they were doing.
They also killed the buffalo that roamed the plains in their millions, shooting them from trains. It was to starve the remaining native populations.