The problem with this scenario of Religious differences being a cause is that in the United States, these differences were not segregated sectionally. Oh to be sure the "righteousness of the cause", north or south added to the fervor but they did not cause the civil war to occur. An examination of the religious beliefs of the "Butternuts," and the First and Second Great Awakenings reveal that north and south of the 600 mile length of the Ohio River there were almost no differences. The difference was the exclusion of slavery north of the river and its eventual habitation by numerous family farmers and the promotion of slavery south of the river as a means to becoming large land owners. This left the least desireable land to the poor dirt farmers. The rest of the Southern white population had to migrate west in search of viable land where their American Dream could be realized too.
Little noted because it it barely discussed in virtually any history is the rapid settlement of the Southwest Territory. The Northwest Territory and its prescribed settlement-to-statehood policies in the Northwest Ordinance had no counterpart south of the Ohio. The only part of the land ordinance to cross the river was the requirement of 60,000 inhabitants (white or black) needed to apply for statehood.
As a result, the southern states of Kentucky, Tennessee, Louisiana, Alabama, Mississippi, Florida, Arkansas, Missouri and Texas qualified for statehood long before the states north of the Ohio. These states all reached sixty thousand people due to settlement by slave-owners who could bring a great deal of land under cultivation quickly. Those who arrived too late were forced to move on. Indeed, South Carolina's white population decreased in the first decade of the 19th century. As an example of what happened to those who moved north and south of the river, Lincoln and Davis were both born in Kentucky in 1809. Neither's father was among the lucky first arrivals. Lincoln's father moved north of the river, where there was plenty of land still available from the government being sold in small parcels (640 acres). Davis' father moved to Mississippi where all the land was in private hands and there was no limit on the amount of land one could buy. Slaves could even be rented on credit to clear the land and put in crops to get started.
This question of 'free soil' which prevented the well-financed from buying up all the good land before the small farmer could even get there is the real heart of this conflict, not religious differences.
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