Prior to 1018, Count Dirk III was a vassal of Henry II, but the bishops of
Trier,
Utrecht and
Cologne all contested the ownership of Dirk's fiefdom, which was in a strategically important location.
Utrecht, situated in the
Rhine delta, was the largest trading town of the German kings in the area and traders had to sail through the territories of Dirk III, by way of the Rhine and
Vecht rivers, in order to reach the
North Sea. Also, the German kings and emperors were frequently resident in Utrecht and the nearby estate of
Nijmegen. Another trade route that ran through Dirk's territory was from the city of
Tiel to England. It was along this second route that Count Dirk built a stronghold at
Vlaardingen, in a newly habitable area where many Frisians had recently settled by his invitation. He was not permitted to levy tolls or hinder trade in any way, but eventually he defied imperial rule. Working together with the Frisians now living in the area, he stopped passing ships, demanding payment of tolls. Merchants from the town of
Tiel sent alarmed messages to the king and
Bishop Adelbold of Utrecht about acts of violence against them by Dirk's men. Emperor Henry then decided to end Dirk III's reign and awarded his lands to Bishop Adelbold. == The Battle of Vlaardingen and its aftermath ==