Twelve years after the founding of the Synod of the Western Reserve in northeastern Ohio, the General Assembly of the Presbyterian Church in the United States of America voted in 1837 to remove that Synod together with three other synods in Western New York, their members, churches, and presbyteries bodily from the denomination, treating the synods and their constituents as if they had never existed. In a time of rapid growth, enthusiastic change and optimism about the nature of the federal union, this church body turned its back on its own union and growth, choosing a path that ultimately caused it to be reduced by nearly half its former membership, and a new denomination to be formed of the exscinded portions together with like-minded others. This new denomination had the same name as the body that rejected it, but was popularly known as the New School of the Presbyterian Church.
Many who wrote about this incident, both contemporaneously and subsequently, attributed the schismatical decision to differences in doctrine, theology, or governance. Relatively few noted the overarching societal concern about chattel slavery, the role of the church in sustaining or removing slavery from the country, and the way in which agitation over slavery and anti-slavery affected both individual church members and the institutional church.
In the early 21st century, the Presbyterian Church (U.S.A.), together with other Protestant denominations, faces schism over the ordination of active homosexuals. Parallels between the two eras are used to shed light on the earlier split, with analyses of the nature of believers who are Presbyterian, insights from earlier Presbyterian church history, a close reading of the General Assembly actions from 1834 through 1837, and a review of anti-slavery agitation found in contemporary religious newspapers. The conclusion reached is that considerations surrounding slavery became key for conservatives in their successful strategy to take over the church and assure that the chaotic frontier could no longer control the Presbyterian Church.