Some four centuries ago, the nations of the Haudenosaunee, or Iroquois, people united in a confederacy to establish peace in what is now upstate New York. The system of unified governance between the Mohawk, Seneca, Onondaga, Oneida, Cayuga and eventually the Tuscarora people enabled the Iroquois to become arguably the predominant Native American tribe in the northeastern United States prior to the arrival of European colonists.

The similarity between the Iroquois federal-style government and the one the American colonists settled on after they wrote the Constitution has long intrigued historians. Could the Iroquois system of governance have been the inspiration for the United States’ newborn republic?

Interest in this question crescendoed around the time of the 1987 bicentennial of the U.S. Constitution. Historians held conferences to sift through the evidence, and the U.S. Senate passed a resolution saying that "the confederation of the original 13 colonies into one republic was influenced by the political system developed by the Iroquois Confederacy, as were many of the democratic principles which were incorporated into the constitution itself."

The topic has proven to be a polarizing one. Some supporters of the notion of Iroquois influence say that the historical establishment is reluctant to give Native Americans credit where credit is due. Skeptics counter that the evidence is largely circumstantial.

"On balance, the consensus appears to be that although British North Americans were certainly aware of the confederal nature of the Iroquois government, the case for causation has not been made," wrote Alison LaCroix, a law professor at the University of Chicago, in The Ideological Origins of American Federalism, published in 2010.