Saxony was in that year attacked by the Prussians, and with so much success that not only was the Saxon army forced to capitulate at Pirna in October, but the elector, who fled to Warsaw, made no attempt to recover Saxony, which remained under the dominion of Frederick.
Corps up the Elbe to Pirna and KOnigstein to cover the fortifications of Dresden itself.
Then hearing that the Austrians had counter-marched and were again moving towards Dresden, he hastened back there, concentrated as many men as could conveniently be handled, and advanced beyond Pirna and KOnigstein to meet him.
At Pirna the Elbe leaves behind it the stress and turmoil of the Saxon Switzerland, rolls through Dresden, with its noble river terraces, and finally, beyond Meissen, enters on its long journey across the North German plain, touching Torgau, Wittenberg, Magdeburg, Wittenberge, Hamburg, Harburg and Altona on the way, and gathering into itself the waters of the Mulde and Saale from the left, and those of the Schwarze Elster, Havel and Elde from the right.
At Pirna (and Lilien stein) in 1756 he caught the entire Saxon army in his fowler's net, after driving back at Lobositz the Austrian forces which were hastening to their asistance; but only nine months later he lost his reputation for " invincibility " by his crushing defeat at Kolin, where the great highway from Vienna to Dresden crosses the Elbe.