The combat of Weissenfels (29 April 1813) was one of the first clashes between Napoleon's new army of 1813 and the advancing Prussian and Russian forces, which by late April had reached the Saale River in Saxony (War of Liberation).
After the disaster in Russia in 1812 Napoleon returned to France to raise a new army. Prince Eugène de Beauharnais ended up in charge in Germany, and was eventually forced back to the line of the Elbe and Saale. The Allies advanced slowly across Saxony, and by late April the main Allied army, under Wittgenstein, was around Leipzig, with outposts on the River Saale, west of the river.
Napoleon had decided to concentrate around Leipzig and move east to cut the Allied lines of communication at Dresden. His new Army of the Main approached from the west and south-west, while Prince Eugène advanced from the north-west.
On 29 April Souham's division from Ney's III Corps (Army of the Main) advanced towards Weissenfels, on the Saale to the south-west of Leipzig. The Russian advance guard cavalry, General Lanskoi's force from Wintzingerode's corps (including a Cossack detachment under General Ilovaysky) fought a delaying action, but was unable to stop the French from capturing Weissenfels.
Further to the north Prince Eugène's troops drove a Prussian detachment sent by Yorck out of Merseburg. The two French armies were thus ready to cross the Saale and advance on Leipzig. On 1 May Napoleon's main army fought a second minor action, at Poserna, east of Weissenfels, notable mainly for the death of Marshal Bessières. On the following day the two sides clashed in the first major battle of the campaign, at Lützen (2 May 1813), and the Allies were forced to retreat back east across the Elbe.