This research offers a religio-sociological and historical analysis of public portents during the Roman Republic, addressing significant gaps in modern scholarship regarding official divination (prodigia, exta, and auspicia). Moving beyond traditional views that reduce Roman divinatory practices to simple political manipulation or irrational mass hysteria, the study demonstrates that public portents operated as a crucial, institutionalized system integral to maintaining the pax deorum and societal stability. By integrating critical source analysis with sociological frameworks—drawing upon theories from Durkheim, Berger, Luckmann, and Assmann—the inquiry demonstrates how the reporting, interpretation, and expiation of omens functioned as a dynamic religio-political process. Central to this mechanism was the interaction between magistrates, the Senate, and priestly colleges, which collectively regulated public order and reinforced state authority. Furthermore, the work highlights the role of divination in shaping Roman identity and expanding Roman influence across Italy. Ultimately, public divination emerges not as a set of empty formalistic rituals, but as a coherent, rationalized system of thought that constructed and maintained the Roman socio-political reality.