Between 1012 and 1018 Thietmar, while Bishop of Merseburg, composed his chronicle
Chronicon Thietmari, which comprises eight books, that cover the period between 908 and 1018, the Saxon Emperors
Henry the Fowler, the three Ottos, and
Henry II the Saint. As counsellor of the Emperor and participant in many important political transactions he was well equipped for writing a history of his times. The first three books, covering the reigns of Henry I and the first two Ottos (
Otto I and
Otto II) are largely based on previous chronicles, most of which are still extant (e.g.
Widukind of Corvey's
Res gestae Saxonicae, the
Annales Quedlinburgenses and others); the fourth book, comprising the reign of
Otto III contains much original matter; while the remaining four books, which describe the reign of Henry II to the year 1018, are the independent narrative of Thietmar and, besides being the principal source for Saxon history during the reign of Henry II, contain valuable information not found elsewhere regarding the contemporary history and civilization of the
Slavic tribes east of the
river Elbe, as well as
Poles,
Hungarians and
Bulgarians. The surviving
manuscript shows ongoing amendments and insertions by Thietmar after the text's completion. The 1913
Catholic Encyclopedia criticizes the style and composition of the writing, as well as the indiscriminate inclusion of unimportant events, but nevertheless recommends it as a historical source on the
Saxony during the reigns of the emperors Otto III and Henry II. It contains a detailed history of the
Bishopric of Merseburg, and of the wars against the
Wends (Polabian Slavs) and the Poles. The original manuscript was moved in 1570 to
Dresden. When the city was destroyed by
bombing during World War II the manuscript was severely damaged, and only a few folios remain intact. Fortunately, a complete
facsimile edition had been published by L. Schmidt (Dresden, 1905). Thietmar's statement that the
Gero Cross in
Cologne Cathedral was commissioned by
Archbishop Gero, who died in 976, was dismissed by art historians, who thought he meant another cross, until the 1920s, and finally confirmed as correct in 1976 by
dendrochronology. ==Editions and translations of Thietmar's Chronicle==