What to read after History, Manners and Customs of the Indian Nations Who Once Inhabited Pennsylvania and the Neighboring States?

From the Introduction: "The reader of the following pages, having already seen what has induced me to come forward with an historical account of the Indians, after so many have written on the same subject, will perhaps look for something more extraordinary in this than in other works of the kind which he has seen. Not wishing any one to raise his expectations too high, I shall briefly state that I have not written to excite astonishment, but for the information of those who are desirous of knowing the true history of those people, who, for centuries, have been in full possession of the country we now inhabit; but who have since emigrated to a great distance."