The Milan-based publishing firm Sonzogno was an essential yet historically overlooked cultural player in nineteenth-century Italy. Positioning Sonzogno as both exceptional in its commercial success and emblematic of an entire cultural landscape, The Periodical Life of Modernity investigates the emergence of modern print culture in Italy and underscores the significance of periodicity as a key lens for understanding this transformative period. Combining archival research, media studies, digital humanities tools, and a historical approach to ideas, technologies, and texts, The Periodical Life of Modernity illustrates how Sonzogno helped establish Italian print modernity, contributing to a new professional role for the publisher, a reconfiguration of the notion of news and of the role of readers in the public sphere, an aggressive interaction with the international print market, and an exponential development of the musical publishing business. Analyzing the extraordinary output of Sonzogno's Stabilimento - from illustrated book series to satirical weeklies, from national dailies to musical collections - The Periodical Life of Modernity offers a new understanding of the role of commercial publishers within Italian culture, as well as a critical discussion on what accessibility, democratization, and the "popular" really mean.