MANSFELD, ERNST, GRAF VON (c. 1580-1626), German soldier, was an illegitimate son of Peter Ernst, Fiirst von Mansfeld, and passed his early years in his father's palace at Luxemburg. He gained his earliest military experiences in Hungary, where his half-brother Charles (1543-1595) held a high command in the im perial army. He allied himself with the Protestant princes, and was despatched by Charles Emmanuel, duke of Savoy, at the head of about 2,000 men to aid the revolting Bohemians at the out break of the Thirty Years' War in 1618. He took Pilsen, but in the summer of 1619 he was defeated at Zablat; after this he offered his services to the emperor Ferdinand II. and remained inactive while the titular king of Bohemia, Frederick V., elector palatine of the Rhine, was driven in headlong rout from Prague. Mansfeld was appointed by Frederick to command his army in Bohemia, and in 1621 he established himself in the Upper Palatin ate, successfully resisting the efforts made by Tilly to dislodge him. From the Upper he passed into the Rhenish Palatinate. Here he relieved Frankenthal and took Hagenau; then, joined by his mas ter, the elector Frederick, he defeated Tilly at Wiesloch in April 1622 and plundered Alsace and Hesse. Mansfeld's ravages were
ruinous to the districts he was commissioned to defend, and at length Frederick was obliged to dismiss Mansfeld's troops from his service. Joining Christian of Brunswick the count then led his army through Lorraine, devastating the country, and in August 1622 defeating the Spaniards at Fleurus. He next entered the service of the United Provinces. A mercenary and a leader of mercenaries, Mansfeld sold his services to the highest bidder. About 1624 he paid three visits to London, where he was hailed as a hero. James I. was anxious to furnish him with men and money for the recovery of the Palatinate, and in January 1625 Mansfeld and his army of "raw and poor rascals" sailed from Dover to the Netherlands. On the renewal of operations in Ger many in the autumn Mansfeld was again engaged. Defeated by Wallenstein at Dessau (1626), he raised another army, and pur sued by Wallenstein he pressed forward towards Hungary, where he hoped for aid from Bethlen Gabor, prince of Transylvania. But Gabor made peace with the emperor, and Mansfeld was com pelled to disband his troops. He died at Rakowitza Nov. 20, 1626. See F. Stieve, Ernst von Mansfeld (Munich, 189o).