Around 1850 the South was an export driven economy based on trade, in particular with Great Britain. By this time New England the whole Northeast had shifted toward a more diversified economy, and native manufacturers militated for the tariffs which their forebears would have scoffed at. Additionally, around 1800 New England was the redoubt of orthodox Christianity. The South was the domain of more easy-going religion, and outright heterodoxy among its social & political elites. Finally, one of the most interesting things to note is that it was in the Southern states that Francophilia during the period of the French Revolution was strongest!
There's a lot to be discussed here. I have not heard of this book. Thanks to Secular Right for this short overview, it sounds like interesting reading. If I were not in the middle of some other reading at the moment, I would look at this book with great interest.