The combat of Altenburg (the next Lasalle project) was a fighting retreat, fought bewteen a French force commanded by Lefebvre-Desnouettes and composed mainly from cavalry (6,000 men) and the Streifcorps of Thielmann and Platov (5,500 men), also composed almost exclusively by cavalry. I have collated a summary of the real combat, with the help of the kindly members of the Napoleon-Series Forum that provided me with very useful information, including scaned copies of some books not available in internet. My acnowledgement to all the members of that Forum, and mainly to Hans - Karl Weiss and Steven H. Smith.
The combat of Altenburg (September 28, 1813)
The Allied devised an attack plan on Altenburg, with three columns: Right (Illesky) advancing by the route of Penig; Center (Kudachev) advancing from Waldenburg; Left (Thielmann and Mensdorff) advancing from Zwickeau. The attack would start from the right with Illesky trying to cut the French retreat upon Borma. He and Kudachev (both under Platov) would menace the French retreat upon Borma or Pegau, while Thielmann (with Mensdorff) would menace the French line towards Zeitz.
The three columns would start from a distance of 4 km from Altenburg and the attack will start at 10.00 a.m.
However, this sound plan was not applied. Platov attacked Altenburg at 7.00 a.m. with Illesky and Kudachev, only to find that Lefevbre-Desnouettes, warned by two Austrian prisoners, had already evacuated the village only fifteen minutes before.
Lefevbre-Desnouettes took a first defensive position at Oberlodla with the artillery and cavalry in the centre and the infantry in the flanks (Molbitz and Schlauditz) but the cossacks soon turned his left and he retreated again to Schelditz. In that village there is a defile formed by the Gerstenbach (stream) and a bridge. The rearguard (Piré’s brigade) made some charges to protect the retreat of the French column and at last, it retired protected by a company of the Baden battalion, which held the bridge until forced to surrender after being encircled by the Allied cavalry.
Meanwhile, Mensdorff and Thielmann warned by the sound of guns, arrived to Altenburg at 7.00 a.m. They advance against the right flank of Lefevbre-Desnouettes, where some squadrons were protecting the retreat of the main column. After some combats involving the Prussian and Austrian cavalry (from the corps of Thielman, Mensdorff and Platov) versus the French cuirassiers (Quinette) and Young Guard Grenadiers and Lancers supported by the Baden infantry, the French cavalry retired towards Bockwitz (near the Messelwitz-Zeitz highway) joining the main column, while the remnants of the Baden infantry were taken at Meusselwitz.
The French retreat continued towards Zeitz. Lorge placed 3 guns and the his 3/35 Légère at a height in front of the town to cover the pass of the Lefebvre-Desnouettes’s division over the Elster bridge, which took about 1 and 1/2 hours. The last squadron of the Grenadiers à Cheval of the Guard broke thorough the infantry and caused disorder which was exploited by Austrian cavalry which rushed into town taking the 3 guns.
Some French infantry resisted in a factory near the bridge until forced to surrender by the Allied. After crossing to the left bank of the Elster, the French were allowed to retire almost unmolested.
The French losses (acknowledged by Lefebvre-Desnouettes) were
Brigade Pire 12 killed, 144 wounded or prisoner
1st Guard (YG) Lancers 38 killed, 52 wounded or prisoner
Gd Chas a Chev. 38 killed, 49 wounded or prisoner
Gd Gren a Chev 15 killed, 40 wounded or prisoner
2nd Baden Infantry regiment 417 wounded or prisoner
3/35 Legere IR - 12 killed, 400 wounded or prisoner