As a brigadier, Lacy bore a distinguished part in the battles of Reichenberg and of Prague, and in all the operations consequent to the invasion of Bohemia by Frederick the Great, whose policy it was ever to keep the scene of his wars as far as possible from his own territory; thus his army entered the Bohemian frontier in four columns, from Saxony, Misnia, Lusatia, and Silesia, under himself and Marshal Keith; Prince Maurice, of Anhalt Dessau; Prince Ferdinand, of Brunswick-Bavern; and the aged Marshal Schwerin. The division of the latter entered in five brigades, at five different places, and won the dangerous defile of Gulder Oelse from the Pandours, at the point of the bayonet. Everywhere the Austrians were driven back before this sudden torrent of Prussian soldiers, who advanced against the position of Count Konigsegg at Reichenberg, where 28,000 men were formed in order of battle, under cover of strong redoubts, and among steep mountains covered with dense forests. But the lines were stormed and the Austrians defeated, with the loss of 1000 killed, among whom were two counts, a prince, and a general, while twenty officers, four hundred soldiers, and three standards were taken as an augury of greater victories. On hearing of this defeat, Leopold Daun marched with all speed from Moravia to reinforce the main body of the Austrians, which, when joined by the regiments of Prague and Bavern, mustered 100,000 men. Making a feint towards Egra (which drew off 20,000 Austrians in _that_ direction), the King of Prussia and Marshal Keith marched against the other troops of the Empress-Queen; and, crossing the Moldau on the 5th May, turned the flank of the Imperialists, under the famous Ulysses Count Brown, whose steady defence made the Prussians waver and fall back. On this the venerable Marshal Schwerin, then in his eighty-second year, stung by the unmerited reproaches of the king, who urged him to advance, dismounted in the marshy ground, and taking an infantry standard in his hand, cried, "Let all brave Prussians follow _me_!" But at that moment an Austrian bullet pierced his breast; and falling thus, covered with years and glory, he closed a long career of faithful military service; but the Prussian foot pressed furiously on, and after three charges totally routed the Austrians, whose general, Count Brown, also received his mortal wound, as already related. Finding the day irreparably lost, Count Lacy, Prince Charles of Lorraine, the Princes of Saxony and Modena, and the Duke d'Aremberg, with the remnant of their infantry, in all 50,000 men, took refuge in Prague, where the gallant Brown expired of his wound, on the 6th May. Meanwhile 16,000 cavalry fled to Marshal Daun, who had encamped at Bohmishbrodt the night before the battle.