The Liber Pontificalis (Latin for 'pontifical book' or Book of the Popes) is a book of biographies of popes from Saint Peter until the 15th century. The original publication of the Liber Pontificalis stopped with Pope Adrian II (867–872) or Pope Stephen V (885–891), Although quoted virtually uncritically from the 8th to 18th centuries, the Liber Pontificalis has undergone intense modern scholarly scrutiny. The work of the French priest Louis Duchesne (who compiled the major scholarly edition), and of others has highlighted some of the underlying redactional motivations of different sections, though such interests are so disparate and varied as to render improbable one populariser's claim that it is an "unofficial instrument of pontifical propaganda."
Authorship
thumb|right|[[Rabanus Maurus (left) was the first to attribute the Liber Pontificalis to Saint Jerome.]]
During the Middle Ages, Saint Jerome was considered the author of all the biographies up until those of Pope Damasus I (366–383), based on an apocryphal letter between Saint Jerome and Pope Damasus published as a preface to the Medieval manuscripts. Most scholars believe the Liber Pontificalis was first compiled in the 5th or 6th century.
Because of the use of the vestiarium, the records of the papal treasury, some have hypothesised that the author of the early Liber Pontificalis was a clerk of the papal treasury.
Duchesne and others believe that the author of the first addition to the Liber Pontificalis was a contemporary of Pope Silverius (536–537), and that the author of another (not necessarily the second) addition was a contemporary of Pope Conon (686–687), with later popes being added individually and during their reigns or shortly after their deaths. As enlarged in the 6th century, each biography consists of: the birth name of the pope and that of his father, place of birth, profession before elevation, length of pontificate, historical notes of varying thoroughness, major theological pronouncements and decrees, administrative milestones (including building campaigns, especially of Roman churches), ordinations, date of death, place of burial, and the duration of the ensuing sede vacante. and Watterich attributed the biographies of Gregory VII, Victor III, and Urban II to Petrus Pisanus, and the subsequent biographies to Pandulf. These biographies until those of Pope Martin IV (1281–1285) are extant only as revised by Petrus Guillermi in the manuscripts of the monastery of St. Gilles having been taken from the Chronicle of Martin of Opava.