the "five fundamentals": the deity of Christ, the Virgin Birth, the vicarious atonement, the inerrancy of Scripture, and Christ's miracles and resurrection. This move against modernism caused a backlash in the form of the Auburn Affirmation — a document embracing liberalism and modernism. The liberals began a series of ecclesiastical trials of their opponents, expelled them from the church and seized their church buildings. Under the leadership of J. Gresham Machen, a former Princeton Theological Seminary New Testament professor who had founded Westminster Theological Seminary in 1929, and who was a PCUSA minister, many of these conservatives would establish what became known as the Orthodox Presbyterian Church in 1936. Although the 1930s and 1940s and the ensuing neo-orthodox theological consensus mitigated much of the polemics during the mid-20th century, disputes erupted again beginning in the mid-1960s over the extent of involvement in the civil rights movement and the issue of ordination of women, and, especially since the 1990s, over the issue of ordination of homosexuals. Mergers The Presbyterian Church in the United States of America was joined by the majority of the Cumberland Presbyterian Church, mostly congregations in the border and Southern states, in 1906. In 1920, it absorbed the Welsh Calvinist Methodist Church. The United Presbyterian Church of North America merged with the PCUSA in 1958 to form the United Presbyterian Church in the United States of America (UPCUSA). Under Eugene Carson Blake, the UPCUSA's stated clerk, the denomination entered into a period of social activism and ecumenical endeavors, which culminated in the development of the Confession of 1967 which was the church's first new confession of faith in three centuries. The 170th General Assembly in 1958 authorized a committee to develop a brief contemporary statement of faith. The 177th General Assembly in 1965 considered and amended the draft confession and sent a revised version for general discussion within the church. The 178th General Assembly in 1966 accepted a revised draft and sent it to presbyteries throughout the church for final ratification. As the confession was ratified by more than 90% of all presbyteries, the 178th General Assembly finally adopted it in 1967. The UPCUSA also adopted a Book of Confessions in 1967, which would include the Confession of 1967, the Westminster Confession and Westminster Shorter Catechism, the Heidelberg Catechism, the Second Helvetic and Scots Confessions and the Barmen Declaration. An attempt to reunite the United Presbyterian Church in