In the late 1970s, the Presbyterian Church in America began the consider what would become an invitation to the Orthodox Presbyterian Church and the Reformed Presbyterian Church, Evangelical Synod to be organically joined and received with the PCA. The RPCES would join the PCA in 1982.

A few years ago, I came across a pamphlet from 1979 at pcahistory.org that included the map below of how the PCA, OPC, and RPCES were geographically distributed at the time.

This geographically is inextricably linked to the history of these three denominations; it is interesting to consider how this distribution developed, and how it has evolved in the last 40 years.