I'm really most interested in the last part of my question. Did any of the books they presumably read on the subject have major biases that today are contradicted what we think about the civil war? I assume the english civil war had passionate defenders and critics of each sides actions during it? What schools of thoughts on the subject were most common among the well read americans? Did this differ than what those in England thought of the civil war?
Cromwell is mentioned by Alexander Hamilton in the Federalist Papers No. 21 Here's an excerpt:
"Without a guaranty the assistance to be derived from the Union in repelling those domestic dangers which may sometimes threaten the existence of the State constitutions, must be renounced. Usurpation may rear its crest in each State, and trample upon the liberties of the people, while the national government could legally do nothing more than behold its encroachments with indignation and regret. A successful faction may erect a tyranny on the ruins of order and law, while no succor could constitutionally be afforded by the Union to the friends and supporters of the government. The tempestuous situation from which Massachusetts has scarcely emerged, evinces that dangers of this kind are not merely speculative. Who can determine what might have been the issue of her late convulsions, if the malcontents had been headed by a Caesar or by a Cromwell? Who can predict what effect a despotism, established in Massachusetts, would have upon the liberties of New Hampshire or Rhode Island, of Connecticut or New York?"