The combat of Berggiesshübel (15 September 1813) was the first step in a French counterattack that restored their position after an Allied attack on 14 September, and ended with some fighting on the southern side of the Bohemian mountains (War of Liberation).
Earlier in September Schwarzenberg's Army of Bohemia had begun an advance on Dresden, with troops on both sides of the Elbe. This forced Napoleon to return to Dresden. The Allies retreated, and by 10 September Napoleon had reached the Geiersberg, on the southern side of the mountain range that divided Saxony from Bohemia. This gave him a chance to attack the Prussian and Russian elements from the Army of Bohemia before the Austrian contigents could reach the area, but he decided that the risk of dropping down to the plains was too great, and withdrew to Dresden. St. Cyr, Victor and Lobau were left to watch the line of the mountains.
Lobau was posted on the French left, on the 'New Road' into Bohemia. His advance guard was at Nollendorf, on the Bohemian side of the border, and the main body of his corps was at the spa town of Berggiesshübel, on the Saxon side.
On 14 September the Allies attacked Lobau's advance guard, and pushed it back from Nollendorf to Berggiesshübel. Lobau managed to hold them up at Berggiesshübel for some time, before he was forced to retreat.
Napoleon reacted quickly to this new Allied advance. He led the Imperial Guard south from Dresden. On 15 September he ordered Mouton-Duvernet's division (42nd Division, from St. Cyr's Corps) to attack via Langenhennersdort and Beraum, to turn Wittgenstein's right, while Lobau's I Corps attacked in the front.
This two pronged assault forced Wittgenstein to retreat to Peterswalde, where he took up a new defensive position. On the following day he was forced to retreat from there as well (combat of Peterswalde, 16 September 1813). This allowed Napoleon to descend from the mountains via the 'New Road', and briefly fight on the plains (Combat of Dolnitz, 17 September 1813).