Battle of the Slaak

The naval Battle of the Slaak was a Dutch victory during the Eighty Years' War. The Dutch prevented the Spanish army from dividing the Dutch United Provinces in two.

In reaction to an overland Dutch attempt to capture Dunkirk earlier in the year, Infanta Isabella Clara Eugenia of Spain, governing the Southern Netherlands for Philip IV of Spain, ordered a Spanish army transported on a fleet of barges to attempt to occupy the islands of Goeree and Overflakee by surprise. In particular, the Spanish wished to overpower the large fortresses on either side of the Volkerak Strait. The fortress on the continental side had special propaganda value, as it was a newly founded town named Willemstad after William the Silent; more importantly, Spanish occupation would have allowed a blockade of the Dutch main naval port Hellevoetsluis located to the direct north of Overflakee on the island of Voorne; and the isolation of the province of Zealand from its confederate provinces.

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