From the very first contacts between Europeans and Amerindians
The British Conquest of the French colonies in North America marked a turning point. King George III issued a Royal Proclamation in 1763 for the administration of British territories in North America, triggering the shift from military and commercial alliances to major land treaties. The road to colonization had to be paved in an orderly and peaceful fashion.
The text of the Royal Proclamation explicitly stated that the consent of Indian
… but that, if at any Time any of the Said Indians should be inclined to dispose of the said Lands, the same shall be Purchased only for Us, in our Name, at some public Meeting or Assembly of the said Indians, to be held for that Purpose by the Governor or Commander in Chief of our Colony respectively within which they shall lie…