Count Leopold Joseph von Daun (; 24 September 17055 February 1766), later Prince of Thiano, was an Austrian field marshal of the Imperial Army in the War of the Austrian Succession and Seven Years' War. Daun is considered one of the outstanding military leaders from his time.
Early years
Leopold Joseph Maria was born at Vienna, the son of Count Wirich Philipp von Daun (1669–1741) and his wife, Countess Maria Barbara von Herberstein (1675–1735). The Daun noble family originated from the Rhineland and derived its name from the ancestral seat at Daun south of the High Eifel range. He was first cousin of Countess Eleonora Ernestina von Daun, who later married the Marquis of Pombal, the noted Portuguese statesman.
He was intended for the church, but his natural inclination for the army, in which his father and grandfather had been distinguished generals, proved irresistible. In 1718 he served in the War of the Quadruple Alliance in Sicily, in his father's regiment. He had already risen to the rank of Oberst (Colonel) when he saw further active service in Italy and on the Rhine in the War of the Polish Succession (1734–35). He continued to add to his distinctions in the Turkish War of 1737–39, in which he attained the rank of Feldmarschallleutnant (Major-General).
War of the Austrian Succession
In the War of the Austrian Succession from 1740, Daun distinguished himself by the careful leadership which was afterwards his greatest military quality.