The Iruquois people are found in North America. They were formerly known as the Five Nations which comprises of Mohawk, Onondaga, Oneida, Cayuga, and Seneca. They however became the Six Nations after accepting the Tuscarora people in 1722. They are primarily known as hunters and farmers and specialize in fur production.
The purpose of dance rituals in Iroquois culture is usually to ensure a good harvest and to appease the spirit of animals in which the dance was performed by the patient and paired conductors, dance leaders, and singers from opposite moieties.
Whites recovered from diseases such as measles and smallpox because their bodies were used to the diseases and their bodies knew how to get rid of them. Native Americans had never experienced diseases like those so their bodies didn't know how to handle them.