Rooted in a series of university lectures, this work is nonetheless simple enough to understand. It is also written well enough that it does not sound like just a transcription. Further, I am almost amazed at how accurate and well a secular historian understands the interplay of faith and practice at the heart of the Puritan experience. In an original review from Harvard, someone called this book "sane, witty, well-balanced, as fresh and readable as a man can make it." I largely agree.
In regards to the actual content, Simpson does a good job showing the fallacy of a human theocracy, whether it is based in the New England wilderness or the old England of Cromwell's day. It is the latter especially that the book excels, tracing the rise of the Puritan hopes and their subsequent fall to pieces on the rocks of human nature. Make no mistake, though based on scholarship, this is not a scholarly book. It is too short and simple for that. But in what it aims to do - acquaint the reader with the broad arc of the Puritan impact on American/English politics and religion - it does a decent job.
This was actually very entertaining! It is based on lectures given in 1954. I learned a lot about Puritans and what motivated them, and certainly see what they have unleashed on America still in overwhelming evidence today. While this book helped to humanize them, their continuing influence on the American character is not a good thing.
Depressing, overall. Author has a begrudging admiration for his subject, but is still in the grip of modernity. Nevertheless, he highlights reasons for the failure of the Puritan experiment.