In very poor circumstances he reached Vienna in 1742, and being furnished with a strong recommendatory letter from the Austrian ambassador, repaired to the Imperial palace in search of military employment. While he was lingering unknown and unnoticed in the ante-chamber, a gentleman accosted him, inquiring his name and business. Loudon having mentioned both, and expressed great desire to see the Empress, this person said, "I will do all in my power to assist you, sir," and passed directly _into_ the cabinet. In a few minutes "Lieutenant Loudon" was summoned by name, and on entering, was astonished to discover in his unknown protector the husband of the beautiful Maria Theresa, Francis Stephen, Grand Duke of Tuscany and First Emperor of the House of Lorraine-Austria! Under auspices so favourable, his request was at once granted, and he obtained a company in the Free Corps of Pandours raised by Baron Trenck, who had known Loudon in Russia, and was well pleased to have under him so gallant an officer. These Pandours were Sclavonians from the banks of the Drave, a river of Germany which rises in the Tyrol and empties itself into the Danube near Effeck in Hungary. This regiment, which was raised chiefly in the village of Pandour or Szent Istevan, wore long coats girt by a waist-belt, in which each man carried a sabre, four or five pistols, and a poniard. On service they always acted as irregular cavalry. This corps had originally been infantry, and were styled the Regiment of Ruitza. Their chief occupation had been to clear the roads of brigands and freebooters; and though the biographer of Baron Trenck endeavours to conceal the fact, history proves that in their new organization the Pandours were a mere military banditti, whose pay was plunder, and whose duty was devastation. Little as he must have liked the service, Captain Loudon commenced a campaign in their ranks, in the war which ensued on Louis XV. and the King of Prussia leaguing together for the partition of the Austrian Empire. A French army under the Marshal Dukes de Belleisle and de Broglie, entered Germany, where the Bavarian Elector formed a junction with them; reduced Lintz, the capital of Upper Austria, and threatened Vienna. Kevenhueller recovered Lintz; the battle of Czaslau, in which the Pandours and Croats charged with such effect and fury was fought; Prague was besieged, and all northern Europe found itself engaged in a general strife. At the head of his Pandours Baron Trenck acted the part of a bold partisan. He stormed the Isle of Rheinmarck, put its garrison to the sword, and with his own sabre slew the commandant, the Comte de Creveceur. Mentzel with four thousand Croats and Pandours broke into Lorraine and Luxembourg, where they committed terrible devastations.