Lack of reliable information on the origins of Neamţ Fortress had resulted in several hypotheses whose reliability was often questioned. A number of historians and philologists, as A.D. Xenopol, B.P. Hasdeu, D. Onciul consider that - according to the papal bull of 1232 - the Teutonic Knights of Bârsa had built between 1211-1225 on the eastern slope of the Carpathians a castrum muntissimum which was later identified as the citadel. The Germanic (Teutonic or Saxon) hypothesis was acquired by many of Romanian historians.