My project is the completion of a book manuscript exploring the diverse uses and interpretations of the SPQR acronym in the politics, ideology, and iconography of medieval and early modern Italy (ca. 600–1600). In the classical period, SPQR was a conventional abbreviation for the formulaic senatus populusque Romanus, referring to the Roman state. By contrast, its contemporary incarnation as Rome’s municipal coat of arms—gold lettering on scarlet—is chiefly a visual, civic symbol. This shift of both form and meaning took place in the Middle Ages, during which the acronym in various forms was used in turn to support imperial, populist, oligarchic, and papal sovereignties over the city. My project on the postclassical afterlife of one of the world’s most famous acronyms will reveal not only the important role played by Roman history in medieval and early modern culture, but also the dense semiotic webs within which that exchange took place.