After the childless death of the last Griffin duke, Bogislaw XIV in 1637, the land again became a "terra" (land, "ziemia") of the Polish Crown and in 1641 became part of the Pomeranian Voivodeship of the Polish–Lithuanian Commonwealth. Whereas the Reformation had been enforced by the Pomeranian dukes, the Poles took action to regain the area for the Catholic Church. After the 1657 Treaty of Bydgoszcz ("Bromberg") that amended the previous Treaty of Wehlau it was granted as a fief to the Hohenzollern dynasty of Brandenburg-Prussia in return for her help against Sweden in the Swedish-Polish War under the same favourable conditions the Griffins had enjoyed before. The Hohenzollern had also acquired the adjacent lands of Farther Pomerania upon the extinction of the line and since 1618 held the Duchy of Prussia in personal union.