 A letter written by John of Rya, the Catholic bishop of Baia refers to Bacău as a "civitas" which implies the existence of a Catholic bishopric in the town at that time.The letter also reveals that Hussite immigrants who had undergone persecutions in Bohemia, Moravia, or Hungary were settled in the town and granted privileges by Alexander the Good.The monastery of Bistrița was also granted the income from the customs house of Bacău in 1439.