From its inception in Zambia in the 1890s, the Catholic Church has always made a tremendous contribution to Zambia's educational enterprise thereby contributing greatly to national development at various levels. However, educational provision in general and Catholic educational provision in particular has always been affected positively or negatively by various factors in the Zambian setting over the years since the inception of Western education by the Catholic Church in the 1890s. A few existing scholars of Catholic education in Zambia have highlighted various reasons showing both negative and positive effects of changes at the social and educational levels on Catholic educational provision over the years in the Zambian setting. This particular article provides a unique engagement particularly with the negative effects of 'social' and 'educational policy' changes on the 'religious mission' of Catholic secondary schooling in Zambia's Southern Province. The article provides a historical analytical perspective of this aspect from Zambia's independence (1964) to date. Any engagement with the primary purpose or the 'religious mission' of such schools entails an inevitable focus on Religious Education (RE), since the subject is the engine for such a mission within Catholic school contexts worldwide. The article's overarching argument is that some aspects of 'social' and 'educational policy' changes experienced in Zambia since independence have negatively affected RE as a curriculum subject specifically in Catholic secondary schools in Zambia's Southern Province to an extent of rendering the subject almost a blatant failure vis-a-vis its 'religious mission' or'religious catechetical message' within the school contexts.