One of the primary objectives of the expedition was to observe the whereabouts of the Indians, what they did, and where they lived. They had to see how many Indian tribes lived in the new acquired land. The expedition met many Indians who offered their supplies. They provided their knowledge of the forest plants and animal types. The Indians also provided weapons and tools for the expedition. They were also given medals and other awards. Most of the encounters with the Indians were friendly while only few were hostile and close to war. The only hostile encounters happened with the Black Buffalo tribe because the chief wanted gifts for passage. They tried to give them gifts but they did not except the gifts. Then Lewis had to display power with the Indians who then excepted the gifts in return they were allowed passage through the river. The expedition thought that the Indian tribe life was harsh and unnecessary to the way they were use to living. By camping near the tribes they had learned the spiritual experiences that the Indians believed they had. The thing that the expedition thought was so alien was that they could have two or more wives than what they were use to. The Indian fathers would often sell their daughters to other men for horses or mules. They saw that many of the tribes were always at war with each other.