 With a similar aim, he attempted to end the long-running conflict with Portugal, allowing it to retain Brazil over the protests of two of the five Netherlands provinces in 1661.The Dutch used the years of peace to build up their commercial fleet again, following its devastation in the First Anglo-Dutch War.De Witt also achieved the post-war completion of many new warships, ordered during the war to augment the existing fleet, including several large ships comparable in armament to the all but the largest English ones.