The argument that John Winthrop was an "indispensible man," worthy of being considered a Founding Father (despite the fact that he was born and died a British subject) is related to his pivotal role in founding the Massachusetts Bay colony. Claims for American exceptionalism, in particular, are often traced to Winthrop's famous entreaty that the Massachusetts Bay Colony should be "as a city on a hill." This claim was reinforced by a number of mid-twentieth Neo-Whigh scholars, most notably Edmund Morgan, whose biography of Winthrop, The Puritan Dilemma emphasized Winthrop's views of the conflict between "the demands of authority and the permissiveness of freedom" as the beginnings of the "development of the American pattern of constitutional and responsible liberty."
This idea has come under attack by historians since the 1970s. Many have pointed out that any claims to an American identity forged in the colonial experience must also take the profoundly repressive and unequal societies in the Chesapeake and Low County South Carolina, as well as the diversity of the middle colonies, into account. Morgan himself, in American Slavery, American Freedom argues that the uniquely racialized notion of liberty that characterized much of American history was born in the Chesapeake. In other words, seventeenth-century laws mandating that African-Americans were consigned to hereditary slavery were as much a part of the American identity as lofty statements about a "city on a hill."
Edmund S. Morgan, American Slavery, American Freedom: The Ordeal of Colonial Virginia (New York: W.W. Norton, 1975)
Morgan, John Winthrop: The Puritan Dilemma: The Story of John Winthrop (Boston: Little, Brown, and Company, 1958)