Which civilization formed a confederation that may have impacted the us government

Iroquois Nation--this nation of tribes created a confederation to settle disputes, facilitate trade, and aid in defense. 

The Iroquois Confederacy consisted of 5 tribes who governed the area of the Great Lakes as a representative unit. Each tribe had delegates who came together to make decisions regarding the group of tribes. This type of confederation is similar to the early government of the US or at least the initial goal--a confederation of states working together on issues that addressed the whole but otherwise independent.