The contents of institutional libraries provide a valuable insight into the cultural and literary aspect of the programme of formation it offered to its students. Much of the material present in the library of the Irish College, Rome dates from the first century of its history. The first direct Irish donor to the College library was Malachy MacBrehun of Kilkenny who died on 3 May 1633. The thirty-eight books he bequeathed to the Irish seminary were delivered to the College on the day after his death. From 1642 onwards, when Jesuit Father Fabio Albergati, cousin of the College founder Cardinal Ludovisi became rector, he and other donors made a series of important gifts of books.  These were volumes in Latin on nearly every  aspect of theological discussion and came principally from the private collection of Father Pietro Farnese and some former alumni, among them John Brennan classmate of the Irish martyr Oliver Plunkett.  The collection includes two thousand volumes from the XVI, XVII and XVIII centuries.  The College library also contains 3 incunabula.

In January, 2008 Laura Lalli and Simona De Crescenzo of the Biblioteca Apostolica Vaticana were engaged by the College to compile a detailed catalogue of the books published prior to 1800 in the College’s possession. This will be of considerable interest to historians studying the intellectual influences experiences by Irish seminarians studying in Rome during the seventeenth and eighteenth centuries. The project will also facilitate the preservation and restoration of these books. The volumes will be catalogued using the ISBD(A) norms and the data stored on computer using the MARC21 format. Lists of donations made to the library will be used to trace the history of each book. Author, title, subject matter, date and place of publication, format, edition, typographical information and inscription, where present, will be among the information recorded. Each volume will be bar coded. The project will be completed by January 2010 and it is being funded by a grant from the Department of Arts, Sport and Tourism.