The town witnessed many wars and uprisings. The nearby Old Prussians besieged the town in 1268 and 1273. Additionally in the 15th century the town experienced the wars between Teutonic Knights and Poland. In 1410 the Polish army took the town and the bishop of Chełmno Arnold Stapil made a tribute to Polish King Władysław II Jagiełło. In 1422 Chełmża was taken again by the forces of the king and destroyed in large part. In 1454, the town joined the anti-Teutonic Prussian Confederation, upon the request of which Polish King Casimir IV Jagiellon re-incorporated the region and town into Poland that same year, what was eventually confirmed following the Thirteen Years' War in 1466. Synods of the Roman Catholic Diocese of Chełmno were held in Chełmża several times between the 14th and 17th centuries. In 1552, Chełmża was visited by Polish King Sigismund II Augustus. After Riga's dissolution in 1566 the bishops of Chełmno attended the councils of the Ecclesiastical province of the metropolitan of Gniezno. This practice was recognised by the Holy See by the Bull "De salute animarum" in 1821, when the Diocese of Chełmno became de jure a suffragan of the Archdiocese of Gniezno. Chełmno diocese was enlarged on that occasion (Górzno, Krajna and Działdowo). In 1621 and 1627 the town hosted the court of Polish King Sigismund III Vasa along with Prince Władysław.