Jeremy Bangs, former Chief Curator of the Plimoth Plantation, Plymouth, MA, has an article discussing the myths about the Thanksgiving holiday. He says the mythsmaking include the United American Indians of New England describing "the ‘first Thanksgiving’ as merely a pretext for bloodshed, enslavement, and displacement that would follow in later decades".
He has an interesting question... in aspiring to discover the true history of an event, "these holidays say much less about who we really were in some specific Then, than about who we want to be in an ever changing Now". By keeping alive our Past does this confine us to only be who our ancestors were? Can we not learn and grow from our Past to be who we truly desire to be? We all desire peace and justice but any study of history shows our ancestors conducted many bloody massacres often in the name of Religion.
Dr. Bangs discusses several sorts of Thanksgiving feasts and celebrations which occurred in the settling of this land by the Europeans. While these feasts were related to other sorts of harvest festivals, to the Puritans 'Thanksgiving' was a specific sort of Religious observance in their cult. He goes into a lot of details and excellent information about several aspects to the history of the Thanksgiving observance.