He was born at St. Petersburg, in the year 1718, and learned the art of soldiering under the eye of his father, and in the camp of Marshal Munich, in the service of the Czarina Anne, during her Crimean and Bessarabian campaigns.
At the age of twenty he was a captain, and to his knowledge and love of the art of war united a polished education, gained under the best masters in Germany.
In 1740, on the accession of Maria Theresa to the Austrian throne, he entered her service, with the permission of the Czarina, and there, by his talents, courage, and gentle bearing won the esteem of his soldiers; thus he soon attained a majority, and then the rank of colonel. He served in the Italian campaign as aide-de-camp to Count Brown, and at Viletri, had three horses shot under him. He distinguished himself still more at the siege of Maestricht, and obtained command of a regiment.
In the war of the Hungarian Succession, after the cowardice and extraordinary mismanagement of the Duke of Cumberland had covered the British army with disgrace in the Low Countries, by allowing it to be outflanked at Khloster Seven, by failing to defend the position at Maestricht, and forcing it shamefully to capitulate, on the 8th of September, 1757, and thus abandon our ally, Frederick the Great of Prussia, that warlike monarch only pushed on the war with greater vigour. In this disastrous contest the activity and vigilance of Count Lacy soon recommended him to the notice of Leopold Count Daun, a native of Bohemia, and son of Philip Lorenzo, Prince of Tiano, the pupil of Kevenhüller; and he improved the good opinion of that great soldier by his fascinating manner and courtier-like behaviour. The friendship of Daun soon won him the rank of major-general; and as such he commanded a brigade in his division, when, in 1757, conformable to the defensive system taken by Russia, Austria, and Sweden, the army of the Empress-Queen was broken into four great columns, to prosecute the war against the Prussians, French, and Bavarians, the violators of the famous Pragmatic Sanction.
One column, under the Duke d'Aremberg, was posted at Egra; a second, under Marshal Count Brown, was posted at Budyn; a third, under Count Konigsegg, held Reichenburg; a fourth, under Marshal Daun, occupied Moravia.
In his column were the brigades of Lacy and Lowenstein, whom Frederick of Prussia styles "two young officers who ardently sought to distinguish themselves." Lacy was then in his thirty-eighth year.
In Lusatia, during the winter of 1756 and the spring of 1757, these officers had given infinite trouble to the troops of Frederick. They had frequently attacked, sword in hand, his post at Ostritz, a Saxon town on the Queiss; at other times, his intrenchments at Hirschfelde, a manufacturing town on the left bank of the Neisse, and also at Marienthiel. Hirschfelde, which was garrisoned by one battalion of Prussians, they assailed at four o'clock one morning, with 6000 men; two redoubts, which stood without the gates, each defended by two pieces of cannon, were repeatedly taken and retaken; but after losing 500 men, Lacy and his brother-brigadier retired, bringing off the Prussian guns as a trophy. These assaults were ineffectual, and many men were slain. Among others fell Major Blumenthal, of the Prince Henry's regiment—a brave officer. The Prussian corps of Lestwitz at Zittace, and of the Prince of Bavern at Gorlitz were harassed by perpetual alarms; and such was the activity of young Lacy and Lowenstein, that they kept them continually under arms, if not in action, during the winter months.
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.