Some of the people who ventured west in those early years lost their lives in attacks by Native Americans. That gave rise much later to the idea that the Oregon Trail was a dangerous place where people we being killed by Native Americans all the time.
It gave rise to the myth that people had to camp inside a circle of wagons in case of attack, and much more.
But while some Native American tribes were aggressive, especially when their land was threatened, many others were not.
