In 173, the Chauci attacked what is now called Flanders. The governor of Gallia Belgica, Didius Julianus, defeated them. The Roman government responded by building several forts along the coast of what is now Zuid-Holland, Zeeland and West-Vlaanderen.The presence of a fort at the island Noord-Beveland can be deduced from Roman roof tiles found at a place called De Roompot.
It is likely that the original fort was at some stage replaced by a heavily fortified castle, and we may assume that this happened in the fourth century.