The battle of St. Dizier (26 March 1814) was Napoleon's last battle during the campaign of 1814, and was a meaningless French victory fought while the main Allied armies were heading for Paris.
Earlier in the campaign Napoleon had managed to win some telling victories, but during March his efforts were less successful. In mid-March he abandoned his final attack on Blucher's Army of Silesia, and attempted to hit Schwarzenberg's Army of Bohemia instead. He hoped to get behind Schwarzenberg, but the Austrian was too cautious, and Napoleon ended up running into his entire army at Arcis-sur-Aube (20-21 March 1814). Only Schwarzenberg's caution on the second day of the battle saved Napoleon from a serious defeat.
In the aftermath of this setback Napoleon decided to head east onto the Meuse, where he hoped to gather reinforcements from the besieged border fortresses, and threaten the Allied lines of communications, forcing them to abandon their attack on Paris. From Arcis he moved north-east to Vitry, and then east towards St. Dizier.
Napoleon's plan totally failed. Rather carelessly he sent an uncoded letter to the Empress explaining his plans, and this fell into the Allies hands. Schwarzenberg decided to ignore Napoleon's movement, and instead take his army north to join up with Blucher. The combined Allied army would then be able to act against Napoleon's rear. The Allies then captured more messages, this time informing them that Paris was in a state of panic. Tsar Alexander decided that the time was right for an attack on Paris. Schwarzenberg's army defeated Marshals Marmont and Mortier at La-Fere-Champenoise (25 March 1814), joined up with Blucher, and the combined Allied army were soon outside Paris.
In the meantime General Winzingerode had been sent to follow Napoleon with a mixed force of cavalry and light infantry, with instructions to try and convince Napoleon that the Allies were following him. At first he was successful – when the French first discovered Winzingerode's force Napoleon thought it was Schwarzenberg's advance guard, and the French prepared a large scale attack.
When Winzingerode was first discovered the French were on the left bank of the Marne, the Allies on the right bank. Napoleon ordered his troops to cross the river over the Hallignicourt ford (west of St. Dizier). The French cavalry crossed first, and spread out to the left and right. The infantry followed. Eventually some 30,000 French troops were involved in the battle.
The French began to advance on their left, the flank furthest from St. Dizier. Winzingerode attempted to avoid battle, ordering some of his troops to secure his retreat, while he attempted to rescue the Allied garrison at St. Dizier. This only exposed his column to more danger, and his force was soon broken and fleeing north away from the battlefield. The Allies lost close to 2,000 men in the battle.
The easy victory at St. Dizier helped convince Napoleon that the main Allied armies were gone. On the following day news of the defeat at La-Fere- Champenoise arrived, and Napoleon realised that his enemies were on the road to Paris. The Emperor left St. Dizier at the start of a desperate race west, but on 30 March the Allies attacked Paris and pushed the outnumbered defenders back towards the city walls. King Joseph had already fled, leaving Marmont and Mortier with permission to surrender the city rather than fight through it. That night the Marshals arranged an armistice, and early on 31 March the Allied armies marched into Paris. Napoleon's great gamble had failed, and within a few days he was forced to abdicate for the first time.