Question

could Native Americans become US citizens under the Northwest Ordinance?

Answer 1

Tribes were not ready to give up their lands, particularly the Indians of Ohio. They did not recognize certain treaties made with the United States during the 1780s, and when the U.S. sent soldiers to take their lands, they fought back. The Ohio Indians successfully destroyed two American military expeditions sent to fight them in 1790 and 1791, but they lost a major battle at Fallen Timbers, Ohio in 1794. In the subsequent treaty, the United States forced the Ohio Indians to cede most of their land. This solidified Indian support for the British, who continued to distrust the United States and feared the federal government had designs on Canada.
http://www.mpm.edu/wirp/icw-143.html