dec 31, 1863 - The Sand Creek Masacre
150 Indians killed, after they surrendered most of which were old men, women and children. In the meantime, the cavalry lost only 9 or ten men, with about three dozen wounded. Black Kettle and his wife followed the others up the stream bed, his wife being shot several times, but somehow managed to survive.
Added to timeline:
Destruction of indian way of life