may 17, 1823 - The First Marshall Decision
In order for the Indians to occupied their land then they had to claim it. "...but that legal title was of a lesser kind than a title that European discoverers used by right of discovery." For the Europeans to leave would mean giving the land to the Indians but then an uninhabited region would be lost. The Indians didn't have absolute title but the United States did. Tribal sovereignty was attacked.
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Indians Timeline Project