LIBER PONTIFICALIS, or GESTA P0NTIF1cUM ROMANORUM
(i.e. book of the popes), consists of the lives of the bishops of Rome from the time of St Peter to the death of Nicholas I. in 867. A supplement continues the series of lives almost to the close of the 9th century, and several other continuations were written later. During the 16th century there was some discussion about the authorship of the Liber, and for some time it was thought to be the work of an Italian monk, Anastasius Bibliothecarius (d. 886). It is now, however, practically certain that it was of composite authorship and that the earlier part of it was compiled about 530, three centuries before the time of Anastasius. This is the view taken. by Louis Duchesne and substantially by G. Waitz and T. Mommsen, although these scholars think that it was written about a century later. The Liber contains much information about papal affairs in general, and about endowments, martyrdoms and the like, but a considerable part of it is obviously legendary. It assumes that the bishops of Rome exercised authority over the Christian Church from its earliest days.

The Liber, which was used by Bede for his Historia Ecclesiastica, was first printed at Mainz in 1602. Among other editions is the one edited by T. Mommsen for the Monumenta Germaniae historica. Gesla Romanorum pontificum, Band i., but the best is the one by L. Duchesne, Le Liber ponhificalis: texte, introduction, commentaire (Paris, 1884-1892). See also the same writers Etude sur he Liber pontificalis (Paris, 1877); and the article by A. Brackmann in l-Ierzog-Haucks Realencyklopadie, Band xi. (Leipzig, 1902).