 He fulfilled this task until 1640.After this, he sailed for a while as skipper of a merchant vessel named "De Vlissinge".In 1641, De Ruyter was nominated by the Admiralty of Zeeland to become the captain of the "Haze", a merchant ship converted man-of-war carrying 26 guns, in a fleet under admiral Gijsels formed to assist the Portuguese in the Portuguese Restoration War against Philip IV of Spain, who was also Philip III of Portugal.