Simplify the following text for a Grade 10 native English-speaking person.
Original: During the American Revolution , many Tuscarora and the Oneida sided with the colonists , while the Mohawk , Seneca , Onondaga and Cayuga remained loyal to Great Britain , thereby marking the first major split among the Six Nations .
Simplified: During the American Revolution , many Tuscarora and the Oneida took the side of the colonists , while the Mohawk , Seneca , Onondaga and Cayuga remained loyal to Great Britain . This was the first major split among the Six Nations .