The Splendor and Opulence of the Past traces the career of Jaume Caresmar (1717–1791), a church historian and a key figure of the Catalan Enlightenment who transcribed tens of thousands of parchments to preserve and glorify Catalonia's medieval past in the face of its diminishing autonomy. As Paul Freedman shows, Caresmar's books, essays, and transcriptions—some only recently discovered—provide fresh insights into the Middle Ages as remembered in modern Catalonia and illustrate how a nation's past glories and humiliations can inform contemporary politics and culture.

From the ninth to the sixteenth centuries, Catalonia was a thriving, independent set of principalities within what would become modern Spain. In the wake of the dismantling of its autonomy by the eighteenth-century Spanish state, Catalan scholars looked to the region's medieval independence and wealth as a means of maintaining a distinct Catalan identity and resisting Castilian hegemony. Through their writings and archival investigations, Caresmar and the canons at Santa Maria de Bellpuig de les Avellanes, where Caresmar was abbot, laid the foundations for not only the scholarly exploration of the Middle Ages but also the development of Catalan national sentiment.

Although the eighteenth century is often regarded as a low point for the Catalan language and culture, The Splendor and Opulence of the Past emphasizes the importance of this period's antiquarians to Catalan projects of modernization and economic progress and links their historiography of the Middle Ages to struggles over Catalonia's relationship to the Spanish state over two centuries.