This paper tries to show the development of politicai Catholicism in Europe, in which at thè end of the 19th Century the Christian social direction prevails, and its acceptance in Slovenia in the form of the Christian social movement of Janez Evangelist Krek. Furthermore, it explains and analyses the development of political Catholicism or the Christian social movement in Europe between the two world wars, which was divided into three directions under the influence of three totalitarianisms and a crisis of the liberal democracy: into a traditional, Christian social direction, dedicated to the Rerum novarum encyclical; into a left-wing Christian social direction, which, in fact, separated itself from politicai Catholicism and moved over to socialist views; into a right-wing regressive voluntaristic corporativist direction, which became more and more similar to Fascist social views. All three directions had followers in Slovenia as well. The most original direction was that of the Slovenian Christian socialism which, in an international scale, covered the largest scope among all European nations and whose views and politicai paths led the most to the lefit, since it established the Liberation Front together with the Communists in 1941.