Following adoption of the Land Ordinance of 1785, American settlers began freely moving west across the Allegheny Mountains and into the Native American-occupied lands beyond – land Great Britain had ceded to U.S. control at the end of the Revolutionary War (the Northwest Territory). As they did, they encountered unyielding and often violent resistance from a confederation of tribes. Harmar committed only 400 of his men under Colonel John Hardin to attack a Native American force of some 1,100 warriors, who easily defeated Hardin's forces. At least 129 soldiers were killed. Determined to avenge the defeat, the president ordered Major General Arthur St. Clair, who was serving as the governor of the Northwest Territory, to mount a more vigorous effort by the third quarter of 1791.