Poweshiek came to power, in part, because many of the leaders of his tribe were massacred by a Sioux war party. The Sioux were at war with the Meskwakie (a.k.a, Fox). The two tribes had a long history of aggression towards each other. The latest round of warfare was caused by the violent actions of the chief of Poweshiek’s village, a person of mixed French and Meskwakie blood called Morgan.
To pick up the story immediately after the massacre of the Meskwakie by the Sioux war party, again from Hagan, 1958:
“Not content with the scalps they had taken, the Sioux hovered around the Fox village and kept its inhabitants in a state of panic. Afraid that the Sioux intended to attack them in their lodges, the Foxes appealed to the Indians at the mouth of the Rock River to send reinforcements and canoes to evacuate them. The Indians of Saukenuk rushed two hundred warriors to aid their allies and shifted the Foxes to a point on the west side of the Mississippi opposite Fort Armstrong. Although the tribesmen were clamoring for war, Forsyth managed to restrain them and gladly granted their wish to visit Clark in St. Louis.”