Dances With Wolves is an EXCELLENT movie that accurately portrays the times. That being said, it's not for kids.
The violence is graphic and, at times, perpetrated because of racism, ignorance, or barbarity. A great deal of callous disrespect is shown by soldiers towards the people and animals of the west. There are several scenes of a man naked (we see his back, bottom, chest, legs, and arms) and a woman (we see her back and the sides of her breasts). There is also sex under blankets.
This movie leaves the viewer deeply ashamed of the white presence in the west, but also newly appreciative of those that showed respect. A viewer needs maturity to watch this. Best for 15+