Page "Christian of Oliva" Paragraph 5

The attempts by Konrad of Masovia to subdue the Prussian lands had picked long-term and intense border quarrels, whereby the Polish lands of Masovia, Cuyavia and even Greater Poland became subject to continuous Prussian raids.

Bishop Christian asked the new Pope Honorius III for the consent to start another Crusade, however a first campaign in 1217 proved a failure and even the joint efforts by Duke Konrad with the Polish High Duke Leszek I the White and Duke Henry I the Bearded of Silesia in 122 / 23 only led to the reconquest of Chełmno Land but did not stop the Prussian invasions.

At least Christian was able to establish the Diocese of Chełmno east of the Vistula, adopting the episcopal rights from the Masovian Bishop of Płock, confirmed by both Duke Konrad and the Pope.