The custom of wearing a pennant at the masthead of a man-of-war stems from Tromp's broom and Blake's whip. During the First Anglo-Dutch War (1652–54), Dutch Admiral Maarten Tromp lashed a broom to his flagship's masthead as a sign that he had swept the English off the seas. In reply, English Admiral Robert Blake hoisted a whip to the masthead to signify that he would whip the Dutchman into subjection. However, records show that pennants were in use well before this period as the mark of a warship.