In 1215, the monk Christian of Oliva was appointed a missionary bishop among the Old Prussians, his residence at Chełmno however was devastated by Prussian forces the next year.
În 1215, călugărul Cristian din Oliva a fost numit episcop misionar printre prusacii vechi, iar reședința sa de la Chełmno a fost distrusă de forțele prusace.