The anonymous author of a Latin chronicle, written in Poland in 1112-1116, now generally known as Cronicae et or Gesta ducum sive principum Polonorum.
The fifteenth-century historian Marcin Kromer attributed the chronicle’s authorship to one Gallus, whom he regarded as probably having been a monk. This view has been generally accepted, and the Gesta’s author is known in historiography as Gallus Anonymus. He arrived at the court of Boleslaw III Krzywousty (Wrymouth), the ruler of Poland, before 1110. He probably originated from France (most likely Provence) and reached Poland via Hungary.
The Gesta is the oldest extant narrative source originating in and concerning Poland. It was written about twenty years after the First Crusade (1096-1099), and is a fundamental source, which established a chronology of Polish history focused on the lives of the rulers of the realm, although no precise dates are preserved in the text. The Gesta became the principal source for later authors and historians such as Wincenty Kadlubek and Jan Dlugosz. The Gesta’s third book dwells especially on the wars fought by its protagonist, Boleslaw Krzywousty, against the Pomeranians and Prussians, and reflects the crusading ideology of the leading families of Poland. The sources of the Gesta were oral history and the traditions of the ruling house.