Pan-Indianism is a term that refers to Native American peoples from many different tribes working together as though they were one people.
This idea is fairly new. Before non-Natives came to North America, there were at least 300 tribes and many more smaller groups. Some were allies, but many were enemies. As a result, when non-Natives began attacking Indians or trying to take away their land, tribes sometimes sided with whites against their Indian enemies.
Pan-Indian rights groups, such as the Society of American Indians, first formed in the early twentieth century, when many Indian tribes were living in poverty. At that time, Indians came to realize that their tribal differences were small in comparison to the larger problems of discrimination and destitution that they shared.
Since that time, Native Americans from different tribes have formed many Pan-Indian groups that have had great success in fighting for the rights of all natives.