Following Napoleon’s victory at Lützen on 2 May 1813 Prince Ludwig Pyotr Wittgenstein’s Russo-Prussian army retreated to Bautzen, where it was reinforced by 13,000 Russians commanded by Prince Mikhail Barclay de Tolly.
Napoleon had received reinforcements from France, including a Young Guard division, four Old Guard battalions and two cavalry divisions, and also now had the support of the Saxon Army. He replaced the previous split of his force into separate Armies of the Elbe and Main with a single Army of the Elbe.
It consisted of two wings. The northern one under Marshal Michel Ney contained 79,500 infantry, 4,800 cavalry and 26 artillery batteries. The main body, under the Emperor’s personal command, consisted of 107,000 infantry, 12,000 cavalry and 53 artillery batteries; 19,000 of the infantry and 4,000 of the cavalry were Guards.. His step-son Prince Eugène, who had performed poorly in this campaign, was sent to command in Italy.
Napoleon’s main problem was that his lack of cavalry meant that he was uncertain of the location and strength of the enemy. He deduced that the bulk of the Allied army would fall back on Bautzen, with a portion covering Berlin.
On 12 May the Emperor sent forward a strong reconnaissance force under Marshal Jacques MacDonald in order to find the enemy. Ney’s wing was to prepare to move on Berlin.
Diplomatic negotiations continued. Prince Klemens von Metternich, the Austrian Foreign Minister, offered to mediate, sending delegates to both sides in order to discover what they would offer Austria. Dominic Lieven points out that the Austrian aims of restoring their lost provinces and of restoring the balance of power in Europe were supported by Austria and Russia, but opposed by France.
Napoleon planned to send Armand Caulaincourt, one of his closest diplomatic advisers, to negotiate directly with Tsar Alexander rather than talking via Austria, but Caulaincourt had not departed by 16 May, when MacDonald discovered the enemy at Bautzen.
The Emperor ordered IV (General Henri-Gatien Bertrand, VI (Marshal Auguste Marmont) and XI (MacDonald) Corps to pin the Allies whilst Marshal Charles Nicolas Oudinot’s XII Corps out-flanked them to the south. Ney was ordered to bring his own III Corps and General Jacques Lauriston’s V Corps south. His II and VII Corps were supposed to continue to advance on Berlin, but Ney misunderstood his orders and brought them south; F. Loraine Petre argues that this error was to the French advantage, as it meant that more troops were concentrated against the main enemy force.
Ney’s orders were complicated. On 18 May he was told to march on 20 May as if he were joining MacDonald, but on 21 May to move eastwards towards the enemy rear. Napoleon hoped that this would enable him to force the Allies back towards the neutral Austrian frontier, meaning that they would be either destroyed or forced to surrender.
Napoleon spent 19 May reconnoitring the enemy. They were in a strong defensive position, but he overestimated their strength, thinking that they had 150,000 men rather than the actual 96,000. As Ney was not in position, he decided to fight a battle of attrition on 20 May, before enveloping the enemy the next day. The Allies intended to stand on the defensive at first, before counter-attacking on their right. They expected the French to attack their left, in order to force them away from Austria.
The French artillery bombardment began at noon on 20 May, with the main infantry attack starting at 3 pm. By 6 pm they had captured the city of Bautzen and the Allied front line. The Allies continued to reinforce their left. They knew that Ney was approaching from the north, but greatly underestimated his strength, so ignored him. David Chandler says that ‘Napoleon could hardly have hoped for anything better.’Napoleon’s plan for 21 May was that VI, XI and XII Corps would pin the enemy, Ney’s III Corps would attack the Allied right and Lauriston’s V Corps would block their retreat. This should force them to strip their centre to strengthen their right flank.Bertrand’s IV Corps would deliver the main attack under the supervision of Marshal Nicolas Soult, who had carried out a similar manoeuvre on the Pratzen Heights at Austerlitz in 1805. A reserve consisting of three infantry divisions, one of them Old Guard and the others Young Guard, and three cavalry division, including a Guard one, supported by 80 guns was established.
The pinning attacks were successful. Oudinot’s XII Corps was forced back a little way, but this drew the Allies out of their prepared positions. IV Corps began its attack at 2 pm, supported by a Young Guard division and all available artillery. Prince Gebhard von Blücher’s Prussians were forced back, but he skilfully extracted them. The French attack lost momentum because the terrain made it difficult to move the artillery forward
The only explicit order given by Napoleon to Ney was that he should be at the village of Preititz by 11 am. His chief of staff, Baron Antoine-Henri Jomini, advised him to screen it and advance into the enemy rear, but Ney launched a series of frontal attacks. Lauriston also moved slowly.
The French attacks in the centre was held up until by a gallant Russian defence, but increasing casualties induced the Tsar to allow limited withdrawals from 4 pm. Napoleon, noting that the enemy resistance was weakening, committed his Imperial Guard against the Prussians.
The Allies were now forced to retreat, but Ney and Lauriston’s failure to advance into their rear meant that they were able to do so safely, extracting all their guns, apart from some that had been disabled. A heavy rain storm stopped any pursuit.
Napoleon had again won a battle, but failed to rout the enemy because of the failure of his subordinates to block the enemy retreat and a lack of cavalry to pursue the defeated foe. Both sides suffered about 20,000 men dead and wounded.
 D. Chandler, The Campaigns of Napoleon (London: Weidenfeld & Nicolson, 1966), pp. 888-90.
 F. L. Petre, Napoleon’s Last Campaign in Germany, 1813 (London: Arms and Armour Press, 1974, first published 1912), pp. 100-2.
 D. C. B. Lieven, Russia against Napoleon: The Battle for Europe, 1807 to 1814 (London: Penguin, 2010), p. 317.
 Petre, Napoleon’s Last Campaign in Germany, 1813, p. 107.
 Chandler, Campaigns, p. 890.
 Ibid., p. 893.