The correct answer is "The colonists were upset because Great Britain had supported and armed uprising of the Cherokee and Catawba Indians against colonial settlements along the frontier."
A big part of the Cherokee tribe allied with Great Britain who had convinced them to fight on their side. Many of the bloodiest battles the Carolinians took up, ended up being against cherokees who got out of hand and started not only attacking Patriots but causing havoc all over the frontier. In the end, South Carolina led a successful campaign against the indians and regained control of the region.
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