Petrarch (1304–1374) aimed to establish a transnational and transtemporal community that could bring together authors from different epochs and regions by imitating the idealised ancient Greek and Roman world, overcoming the supposedly obscure Middle Ages. The first part of this case study shows how Petrarch's vernacular lyric poems Rerum vulgarium fragmenta were employed to foster concrete Gesellschaften and give rise to diverse cultural communities through two commentaries on the RVF, composed in Naples in the 1470s. The second part of the study delves into Petrarch's efforts to build community within the Latin dialogue De remediis utriusque fortunae, with particular emphasis on a sixteenth-century German print edition. The conclusion addresses the impact of Petrarch's role in building communities during the early-modern period.