From then on Utrecht became one of the most influential seats of power for the Roman Catholic Church in the Netherlands.
The archbishops of Utrecht were based at the uneasy northern border of the Carolingian Empire.
These fortresses were designed to house a cohort of about 500 Roman soldiers.
Near the fort, settlements would grow housing artisans, traders and soldiers' wives and children.
The prince-bishopric was involved in almost continuous conflicts with the Counts of Holland and the Dukes of Guelders.The tenure of Willibrordus is generally considered to be the beginning of the Bishopric of Utrecht.In 723, the Frankish leader Charles Martel bestowed the fortress in Utrecht and the surrounding lands as the base of the bishops.It lost the status of prince-bishopric but remains the main religious centre in the country.
Utrecht was the most important city in the Netherlands until the Dutch Golden Age, when it was surpassed by Amsterdam as the country's cultural centre and most populous city.The choir and transept were finished from 1320 and were followed then by the ambitious Dom tower.