By the early 20th century, though, much of the controversy had been rendered moot by three factors. First, the rise of the strongly Protestant neo-orthodox movement among scholars and some RCUS clergy gained ascendence over the romanticism and metaphysics on which Mercersburg was largely based. Second, the resistance to at least modest liturgical innovations by some Old Reformed parishes gradually disappeared under the influence of the ecumenical liturgical movement. Finally, the RCUS' merger with the Evangelical Synod of North America in 1934 brought a significant pietist constituency to the new denomination, as well as a more mediating approach to doctrine, thereby reducing the polemical style of past generations.