In 1329 Pope John XXII (in captivity in Avignon) erected Quilon as the first Diocese in the whole of indies as suffragan to the Archdiocese of Sultany in Persia through the decree "Romanus pontifex" dated 9th August 1329. By a seperate Bull "Venerabili Fratri Jordano", the same Pope, on August 21,1329 appointed the French Dominican Friar Jordanus Catalani of Serverac as the first Bishop of Quilon.

It is worth noting that Quilon is the only city where both the Apostle St. Thomas and the great missionary of the East St.Francis Xavier spread the Gospel of Christ.