HEYN, PIETER PIETERZOON [commonly abbreviated to PIET] (1578-1629), Dutch admiral, was born at Delfshaven in 1578, the son of Pieter Hein, who was engaged in the herring fishery. The son went early to sea. In his youth he was taken prisoner by the Spaniards, and was forced to row in the galleys during four years. Having recovered his freedom by an exchange of prisoners, he worked for several years as a merchant skipper with success. The then dangerous state of the seas at all times, and the continuous war with Spain, gave him ample opportunity to gain a reputation as a resolute fighting man. Wills which he made before 1623 show that he had been able to acquire considerable property. When the Dutch West India Company was formed he was Director on the Rotterdam Board, and in 1624 he served as second in command of the fleet which took San Salvador in Bahia de Todos os Santos in Brazil. Till 1628 he continued to serve the Company, both on the coast of Brazil, and in the West Indies. In the month of September of that year he made himself famous, gained immense advantage for the Company, and inflicted ruinous loss on the Spaniards, by the capture of the fleet which was bringing the bullion from the American mines home to Spain. The Spanish ships were outnumbered chiefly because the convoy had become scattered by bad management and bad seamanship. The more valuable part of it, consisting of the four galleons, and eleven trading ships in which the king's share of the treasure was being carried, became separated from the rest, and on being chased by the superior force of Heyn endeavoured to take refuge at Matanzas in the island of Cuba, hoping to be able to land the bullion in the bush before the Dutchman could come up with them. But Juan de Benavides, the Spanish commander, failed to act with decision, was overtaken, and his ships captured in the harbour before the silver could be discharged. The total loss was estimated by the Spaniards at four millions of ducats. Piet Heyn now returned home, and bought himself a house at Delft with the intention of retiring from the sea. In the following year, however, he was chosen at a crisis to take command of the naval force of the Republic, with the rank of Lieutenant-Admiral of Holland, in order to clear the North Sea and Channel of the Dunkirkers, who acted for the king of Spain in his possessions in the Netherlands. In June of 1629 he brought the Dunkirkers to action, and they were severely beaten, but Piet Heyn did not live to enjoy his victory. He was struck early in the battle by a cannon shot on the shoulder and fell dead on the spot. His memory has been preserved by his capture of the Treasure Galleons, which had never been taken so far, but he is also the traditional representative of the Dutch "sea dogs" of the 17th century. See de Jonge, _Geschiedenis van het Nederlandsche Zeewezen_; I. Duro, _Armada espanola_, iv.; der Aa, _Biograph. Woordenboek der Nederlanden_. (D. H.)