The Liber Pontificalis is an invaluable historical document, cataloging the names and dates of the first 65 Pontiffs of Rome beginning with St. Peter himself. Though of unknown authorship, its antiquity is well established. Modern scholarship has determined that the Liber was probably first compiled in the 6th century AD and continued piecemeal thereafter. This English edition, originally published in 1916, covers up through the end of the 6th century.

As such, it coincides with the rise of Christianity from the catacombs to become the preeminent faith of the Mediterranean world. It includes significant biographies of many noteworthy Popes such as Sylvester, Leo the Great, John I, and Silverius and touches upon the reigns of secular rulers such as Constantine I, Attila, Justinian I, and Theodoric.

The Liber is a valuable source of information on the various heresies of the early Church and the councils called to deal with them. The work also provides archaeological clues about the ecclesiastical monuments of Rome, both those which survive to the present day and those which were destroyed.

Though many of the earliest biographies are brief, devoid of detail and littered with obvious errors, the biographies of the 4th, 5th and 6th centuries are considerably more fleshed-out and of much greater scholarly value. The translator, Louise Ropes Loomis, provides an informative introduction and includes footnotes mainly derived from the authoritative commentaries of Mommsen and Duchesne, two of the foremost 19th century scholars of the Liber. These notes are helpful in identifying and correcting the problematic sections of the work and otherwise providing context. Furthermore, several manuscript traditions have been reproduced in parallel in this edition so that the reader may compare them side-by-side.

The 2006 edition includes 14 black & white illustrations from the lives of various Popes, as well as a short preface.