Over time, traditional Calvinism played less of a role in shaping the church's doctrines and practices—it was influenced by Arminianism and revivalism early in the 19th century, liberal theology late in the 19th century, and neo-orthodoxy by the mid-20th century. The theological tensions within the denomination were played out in the Fundamentalist–Modernist Controversy of the 1920s and 1930s, a conflict that led to the development of Christian fundamentalism and has historical importance to modern American evangelicalism. Conservatives dissatisfied with liberal trends left to form the Orthodox Presbyterian Church in 1936.