Accomodationists rarely mention the history behind the first sentence of Article III of the Northwest Ordinance, and for good reason; the sentence does not reflect either the historical circumstances or the thinking that led to the passage of the Ordinance. Rather, the sentence was inserted into the document at the last minute at the urging of a group of New England land speculators for perfectly idiosyncratic reasons. There is nothing that one can conclude from the sentence except that the Continental Congress would have done anything to please the people they wanted to develop the Northwest Territory.
The New England group, known as The Ohio Company Associates, was a group of Revolutionary War veterans. The leadership of this group was made up by Benjamin Tupper, General Rufus Putnam, Samuel Holden Parson, and its chief agent, the skillful lobbyist Manasseh Cutler, who was an ex-army chaplain. Reverend Cutler was known as that "wheeler-dealer" from New England.
The Ohio Associates main business was land speculation, but the management, at least, had a secondary business. This was a time when various states were disestablishing religion, separating civil governments from religion, and granting complete religious freedom to their citizens. The New England States, as a whole, had a history of close involvement between church/state, even to the extreme of having had theocracies in some places in the previous century. To say the least, they were reluctant to embrace the emerging doctrine of church/state separation. They were also extremely fearful of the spread of what they termed "Popery" (i.e. Catholicism). True religious freedom was a scary concept for many people, especially in the New England states. When the ban against religious tests was placed in Article VI of the Federal Constitution (the true separation clause), for example, editorials throughout the New England area bemoaned the fact in almost panic terms.
The Ohio Company Associates were very desirous, at the least, of protecting their religious viewpoints, and possibly spreading it beyond their own state boundaries. What is more, the Associates were in a position to get just about anything they wanted from Congress, since Congress wanted to ensure that Cutler and his group would buy large tracts of land in the Territories. Accordingly, The Ohio Company Associates pressed Congress hard to get both a good deal on the land, and a guarantee that they could implement their own church/state system on this land.
By all accounts they were successful in achieving both goals. With respect to land speculation, historian Richard B. Morris notes the following:
To win a key ally, the associates proposed making General Arthur St. Clair territorial governor. At that time St. Clair was serving as president of Congress....[Note: the President of Congress was the forerunner of President of the United States, and under the Articles of Confederation the holder of this office also had the right to vote as a member of Congress. That meant that whomever held that office not only had the power of persuasion, as did any member of Congress, he also controlled one vote, his own, and had the added prestige of that particular position. That position at that time did not have the full powers or authority that it would gain under the Constitution, as the position of President of the United States, yet it did carry some intangibles as far as "authority" was concerned.]
The deal had smooth sailing. Not only did Cutler's group get the million and half acres but also an option on another five million. As part of the " understanding," St. Clair was elected the first territorial governor, Winthrop Sargent, one of the Ohio Company principles, territorial secretary (The Forging of the Union: 171-1789, p. 228-229).
They were almost as successful in getting Congress to agree to their religious demands. Briefly, because of the influence of the Ohio Company Associates, the New England voting block refused to vote for the Ordinance unless it contained language allowing for some type of religious establishment. Accordingly, only two days before its passage, the following language was written into Article III of the Ordinance:
In the final version of the amendment, however, this strong language calling for the encouragement of religious institutions was dropped in favor of the following:
Hence, the Ohio Company Associates were unable to get everything they wanted. While they were successful in getting Congress to agree that religion and morality were necessary to good government, the language of the ordinance did not explicitly authorize support for religious institutions, or religious instruction in the schools. As constitutional scholar Derek Davis observes, this change in wording "could indicate that at least some members of Congress were at least considering `establishment' overtones; they may have been attempting to ensure that the sustenance of religious life would come from the people and the schools, not from government (Original Intent, p. 108-109).
In summary, there is little evidence that Congress had any particular interest in writing establishment of religion into the Northwest Ordinance. On the contrary, the first sentence of Article III would likely never have been written at all in the absence of the influence of the Ohio Company Associates. Further, the language of the Ordinance was watered down to obscure any direct support for religion. There is nothing in the history of the Ordinance, in other words, to suggest that the first sentence of Article III was either a well thought out policy, or a deliberate attempt by Congress to aid religion.