Almost immediately after the British acquired the region, Pontiac, an Ottawa chief, led an uprising against them (see Pontiac's Rebellion). The Ottawa were somewhat appeased by the British Proclamation of 1763 that closed the region W of the Allegheny Mts. to white settlement in an attempt to protect the Native American fur trade and lands; yet this action caused resentment among the American frontiersmen and contributed to the American Revolution. The mysterious machinations of Robert Rogers, an American frontiersman, further endangered the British hold on the Old Northwest. During the Revolutionary War, an expedition led by the American general George Rogers Clark penetrated deep into the region in 1778–79, in one of the most daring and valuable exploits of the war.