In the summer of 1791, attacks on settlers in the Northwest Territory intensified, culminating in one of the greatest defeats ever suffered by the U.S. Army. The violence had been attributed exclusively to northern tribes, but in advance of the next battle, Chickasaw warriors discovered the attacks were being incited by rebel British in a covert effort to reclaim the Ohio Valley. After the Americans won the battle of Fallen Timbers, President Washington awarded three Chickasaw leaders peace medals for their pivotal role in achieving victory for the young republic.