Juan Francisco Pacheco Téllez-Girón, 4th Duke of Uceda (1649–1718), held various posts during the reign of Charles II, among them that of viceroy of Sicily. Although he was ambassador in Rome during the War of the Spanish Succession and defended Philip V’s cause before the Holy See, he subsequently went over to the side of Archduke Charles, as a result of which his property was confiscated in 1711. His books passed to the Royal Library and nearly all of them joined the holdings of the Biblioteca Nacional when it was founded.

This study provides an introduction to the context of printed book culture and the libraries where Uceda engaged in his activity, as well as a biographical sketch of his life. It also reproduces in facsimile an important, hitherto unpublished document written by Uceda in support of Philip V. After analysing the library according to the criteria of its librarian, Ioannes Sylvester, it lists an exhaustive catalogue of his printed books including the CCPB for each entry and the current accession number issued by the Biblioteca Nacional.

Margarita Martín Velasco holds a doctorate in Modern History from the Universidad Complutense in Madrid and is director of the Library at the Centro Universitario Villanueva. She has published various articles on the Spanish War of Succession and on the history of books and libraries. She currently directs the library at the Centro Universitario Villanueva, which is attached to the Universidad Complutense.