Final answer:
The Iroquois Confederacy, comprising the Mohawk, Oneida, Onondaga, Cayuga, Seneca, and Tuscarora tribes, allied with England during the French and Indian War, solidifying their alliance through the Treaty of Easton in 1758.
Step-by-step explanation:
During the French and Indian War, a number of Indian tribes were allied with different European powers. However, the group of tribes that allied with England was the powerful Iroquois Confederacy, often called the Haudenosaunee. These tribes consisted of the Mohawk, Oneida, Onondaga, Cayuga, Seneca, and later the Tuscarora. This alliance was solidified through the Treaty of Easton in 1758 where the Iroquois, along with the Shawnee and Delaware tribes, agreed to ally with the English in exchange for promises regarding their lands. These strategic alliances were crucial in turning the tide of the war in favor of the British, leading to their ultimate victory over the French in North America.