No tribe has the right to sell, even to each other, much less to strangers... Sell a country! Why not sell the air, the great sea, as well as the earth? Didn't the Great Spirit make them all for the use of his children?
The way, the only way to stop this evil is for the red man to unite in claiming a common and equal right in the land, as it was first, and should be now, for it was never divided. We gave them forest-clad mountains and valleys full of game, and in return what did they give our warriors and our women? Rum, trinkets, and a grave.

As quoted in The Complete Idiot's Guide to the Old West (1999) by Mike Flanagan, p. 94; this appears to contain slight variants of comments reported to have been spoken to William Henry Harrison in August 1810.