Recent archaeological finds indicate that it is built on an early Christian church, dating from around the fourth to fifth century.

The cathedral's bell tower was built in the fifteenth century after a lightning strike destroyed the original Romanesque one.

In the second half of the sixteenth century, the apse of the chapel of the Holy Cross and the altar with a colorful late Renaissance wooden crucifix were also added.

It contains liturgical objects and precious relics, including enameled copper plates and the twelfth-century reliquary of St. Christopher.

Between 1997 and 2005, the cathedral underwent extensive renovation awarded with a Europa Nostra Diploma "for the comprehensive research, skillful restoration and didactical presentation of one of Croatia’s foremost medieval monuments".