By the end of World War II, the whole world stepped on a new stage that will affect any countries economically and politically. Turkey although did not involved in the actual war, but had been affected closely, and developed appropriate policies accordingly its’ own situation. Turkey, which looked for a proper position in the new world system emerged after the war, genuinely understood that their single party system would not be sustainable more. İsmet İnönü and the party executives had closely followed the political issues in the World, and they realized the radical changes they have to carry out to be integrated into the new system. In parallel to these changes, the Single Party period, which took twenty- three years, was ended with the new political regulations by the end of 1945. Along with the establishment of opposition parties, CHP apparently had to go through some revisions of their own policies. They therefore understood that the concept of secularism they practiced had to be changed in the new period. They also agreed that this attitude created opposition movements emerging around religious education which remained undeveloped, and they would no longer resist to oppositions’ demand for this issue. After the war, objections to the same issue were raised from both within the party and different social associations and groups. The aim of this study is to understand the debates carried out in the 1947 Congress on "secularism" and more particularly on "religious education". We also aimed to examine how the issues discussed throughout the congress reflect on party politics after the congress. We finally try to understand the internal and external causes drove CHP to these changes and how their internal perspectives changed.