Observing the Roman Catholic Church activities in Yugoslavia for more than fifty years, the author concludes that this Church replaced the idea of service to God by service to the Roman Curia, i.e. service to the government of the Roman Pontificate in the role of the world leader. As a result of this idea, in the Kingdom of Yugoslavia, the Roman Catholic Church identified the Roman Catholicism to the Croatian nationhood, which turned most of its priesthood into ardent Ustashe supporters.