Maurice's army remained in Nieuwpoort for fourteen days, and although his army had driven a Spanish army from the field, a rare feat at the time, the battle achieved little beyond that. The Dutch did not proceed to occupy or even invest Dunkirk, which had been the principal objective of the campaign. Their lines of communication had already been stretched to the limit and Maurice was soon forced to withdraw from the territory of the Spanish Netherlands. The Flemings, whom Maurice had hoped to rally to his revolt, remained loyal to the Spanish monarchy. Dunkirkers would continue to prey on Dutch and English trade. Instead the allied army proceeded to Ostend, where they captured a large Spanish fort named 'Isabella'.