The establishment of the earlier North Atlantic settlements of Virginia and New England predate the concept of the Noble Savage. That's from Jean Jacques Rousseau, who in part was reacting to the heavy formality and mannered structures of French society of the mid-18th century ( that had come about in part from the intricate manners of the court of Louis XIV) . Rousseau felt that primitive peoples were more naturally good , than civilized ones. There were also the earlier writings of John Locke, who founded his ideas of rational government on the cooperative agreements of a hypothesized Primal Horde of early humans on how they should govern themselves. Locke's writings are reflected very strongly in Jefferson's language in the Declaration of Independence, with "governments being instituted among men" for rights of "life, liberty and pursuit of happiness ". There was also the example of the Iroquois Confederation, which, though it was mostly destroyed by the American Revolution, provided an example of Native American cooperative government. You can see some of this reflected in the Constitution, which granted Native American tribes the status of nations.

However, it's hard to see why Ambrose bothered to stress this, because this hopeful rhetoric wasn't really carried out into practice. Though the differences between colonists and Native Americans were complex, essentially the process became pretty simple: the Native Americans were less powerful and always would lose in a dispute, the territory occupied by the Indians was valuable to the colonists and was gradually encroached upon or appropriated, even the lands of those that had largely adopted American ways like the Cherokee. Perhaps someone has a deep analysis of this and the sources, and has a different take on it, but the Noble Savage rhetoric seems to echo some of the paternalistic rhetoric about slavery: a kindly story people tell themselves, so they don't feel too ashamed of what they're really doing.