Berthold of Reichenau, a Benedictine monk and chronicler of the celebrated Abbey of Reichenau on the Lake of Constance; d. probably in 1088. He was a disciple and friend of the learned Hermannus Contractus. When Hermann saw death approaching, he entrusted to Berthold all the wax tablets that contained the writings which he had not yet committed to parchment and commissioned Berthold to peruse them and, after careful revision, to copy them on parchment. Berthold was also exhorted by his dying master to continue the famous world-chronicle, begun by Hermann, which in chronological order related the history of the world from the birth of Christ to 1054, the year in which Hermann died. To the continuation of this chronicle and to a biography of his master and friend, Hermannus Contractus, is due whatever fame is attached to the name of Berthold.
The chronicle, as far as it was written by Berthold, comprises a concise and impartial history of the troublesome times immediately preceding the accession of Gregory VII and probably also of the early reign of this great pontiff. It is reprinted to the year 1080, with an introduction by Pertz, in “Mon. Germ. Hist.: Script.” V, 264-326, and in P.L., CXLVII, 314-442. Pertz contends that Berthold did not begin the continuation of Hermann’s chronicle until 1076, and that in the execution of it he made use of another chronicle, written by Bernold who was also a monk of Reichenau; but it has been proved almost beyond doubt by Giesebrecht and Schulzen that Berthold was the first to continue Hermann’s chronicle and that Bernold’s chronicle is a continuation of Berthold‘s. It is, however, still undecided as to what year Berthold‘s chronicle extends. Ussermann and Schulzen hold that it extends only to the year 1066, while Pertz, Giesebrecht, and others believe that Berthold wrote the chronicle at least to the middle of the year 1080, where the manuscript suddenly ceases in the middle of a sentence.
The original text of Berthold is no longer in existence and all the existing copies have been compiled from various manuscripts found in the monasteries of St. Gall, St. Blaise, Muri, and Engelberg. The chronicle was continued by Bernold to the year 1100, and by others to the year 1175. From various passages in Berthold‘s chronicle it appears that, for a short time at least, he considered Cadalus, Bishop of Parma, as the legitimate occupant of the papal throne; but he soon noticed his mistake and from the year 1070, or even earlier, acknowledged Alexander II as the true pope. Bernold remarks in his chronicle under the year 1088 that Berthold, an excellent teacher who was very well versed in Holy Scripture, died at an advanced age on the 12th of March.