Answer: Sincerity
The Iroquois Confederacy was established by the Peacemaker in 1142. It brought together five nations into the "Great League of Peace." At its peak, the confederacy extended into Canada, along the Great Lakes and down into Virginia, Kentucky and the Ohio Valley.
The excerpt states that "all lords of the Five Nations’ Confederacy must be honest in all things." It states that the quality a leader needs to have is that of honesty, or sincerity.