The Indian Removal Act simply gave the federal government permission to propose treaties to Native Americans for them to sign, giving up their lands. The government would oftentimes offer cheap terms, which would be signed by one faction of a tribe. Most of the tribes did not recognize the signed treaties as official, and refused to leave. This resulted in forced removal. More to the point, the lands fell under federal and state control, but were to be "cleared" (I know, terrible term) for white settlers. Hope this was helpful!