The Florentine Consulte e Pratiche is the oldest recorded series of speech-by-speech policy discussion by political elites in European history, over one hundred and fifty years in length. This article is the first of an extended two-article sequence on political discussion in the Consulte e Pratiche, during the 1376–1378 period of the War of Eight Saints, which led up to the famous Ciompi Revolt. Our interest is in discovering both the semantic-network (article 1) and the factional-network (article 2) mechanics of this unexpected spillover from foreign-policy conflict into domestic revolt. Our central finding at the semantic level, in this first article, is that the spillover from war to revolution was mediated through the ceremonial and political-economy sides of religion.The methodology in this first article is to uncover the evolving narrative-network structures exhibited in Florentine political discussion – namely, changing inter-correlations among keywords about topics, through chapters and subplots. “Narrative-network analysis” for us means (a) uncovering changing topological portraits of how subplots interlink through time, and (b) discovering interlocking linguistic “hinges” through which new historical trajectories of subplot combinations become defined. In our case, the linguistic hinges between foreign policy and domestic revolt were rooted in religion. How the evolving issues and topics discussed in this article express themselves in domestic (and eventually violent) political conflict between the anti-war Parte Guelfa faction and the pro-war Civic ‘faction’ will be the subject of the second of this complementary pair of articles.