After the Revolutionary War, Shawnee of the Ohio Country began to forge a confederacy to oppose U.S. occupation of the land ceded by the British in what became called the Northwest Territory (now Midwest of the United States). These efforts were clandestinely supported by the British, who had refused to abandon Fort Detroit and Fort Mackinac as called for in the 1783 peace treaty with the United States. Egushawa was initially reluctant to take part in the Northwest Indian War, but he joined the native Western Confederacy after the defeat in October 1790 of an American army led by Josiah Harmar .