The battle of Cardadeu of 16 December 1808 was a French victory that ended the Spanish siege of Barcelona. That siege had been underway since early in August, and by December the garrison was running short of supplies. A relief column under General St. Cyr cross the Pyrenees on 5 November, but its first objective had been the town of Rosas, from where the Spanish could have threatened their supply lines. What St. Cyr had expected to be a short siege had dragged on until 5 December, making it increasingly urgent that he reached Barcelona without any further delays.
This would not be easy. There were two good roads that led to Barcelona from the north, the coast road that ran south from Rosas, and the main road. Unfortunately for St. Cyr, the Spanish had effectively destroyed the coastal road, which in any case was within range of British naval guns, while the main road was blocked by the Spanish held city of Gerona. This place had already resisted two sieges, and St. Cyr simply did not have enough time to attempt to capture the place. St. Cyr came up with a bold alternative. On 10 December he appeared outside Gerona at the head of 15,000 infantry and 1,500 cavalry, hoping to convince General Vives, the Spanish commander outside Barcelona, that he was intending to besiege Gerona.
On 11 December St. Cyr put his plan into place. He sent his heavy baggage train, containing his artillery and most of his food and ammunition back to Figueras, and led his men into the mountains between Gerona and the coast. His aim was to travel light through the mountains, first to reach the coastal road from Gerona to Barcelona, and then to swing back inland to the main road close to San Celoni. He hoped to achieve two things with this manoeuvre – first to confuse Vives, and second to bypass the fortress at Hostalrich, which blocked the main road between Gerona and Barcelona. However to do this he had to abandon all but four days of food and sixty rounds of ammunition per man. If he had to fight off too many Spanish attacks in the mountains, or if Vives blocked his route with the main field army, then St. Cyr’s men would have run out of ammunition or food, and been forced to retreat, or in the worst case surrender.
The risk paid off. The only fighting during the time in the mountains came on 12 December when he brushed aside a force of the local miqueletes, and on 15 December the French reached the main road close to San Celoni, 27 miles east of Barcelona on the main road from Gerona. Before camping that night, St. Cyr moved his men south along the road, through the pass of the Trenapassos, bypassing the best defensive position on the road. Meanwhile his actions had given Vives enough reasons to remain inactive at Barcelona, even after he learnt that the French had bypassed Gerona. All Vives did was dispatch a division of infantry under General Reding along the road to Granollers, ten miles from San Celoni, and another small force under General Milans to guard the coast road. This force then crossed the mountains to San Celoni, where on 15 December it was brushed aside by St. Cyr.
When he learnt that the French were at San Celoni, Vives finally moved, but instead of taking his entire field army to join Redes, he left 12,000 men at Barcelona and only took 4,000 to join Redes, catching up with him at Cardadeu. St. Cyr’s 16,500 men were opposed by a Spanish force of 8,400 infantry, 600 cavalry and only seven guns (although St. Cyr had no artillery, having abandoned them on 11 December).
The decisive battle took place on 16 December. Vives formed his men into two lines, running from the river Mogent on the right into wooded hills on the left. Neither Vives or St. Cyr had any time to take up careful positions – Vives only reached the battlefield on the morning of the battle, while St. Cyr was aware that the garrison of Gerona was approaching from the rear. The French were also running short of ammunition, and only had enough shot for one hour of fighting. St. Cyr’s only chance of victory was to form two of his three divisions into a single massive column, and batter his way through the Spanish lines.
Against more experienced troops, this plan could only have ended in disaster, but most of Vives’ men were inexperienced recruits. Even so, the French plan came close to failure. General Pino, whose division made up the head of the column, lost his nerve when he came under fire from the flanks, and instead of attacking in strength at one point, spread his men out across a front three quarters of a mile long. After forcing back the first Spanish line, the French advance ground to a halt. The situation was restored by St. Cyr, who sent his second division into the attack. They broke through the Spanish right, and the rout was completed by a cavalry charge.
The Spanish suffered around 1,000 casualties in the battle, while the French captured 1,500 prisoners. St. Cyr reported his losses at 600, mostly suffered in Pino’s division early in the battle. Vives eventually escaped to the coast, where he was rescued by the frigate Cambrian. Reding was eventually able to restore some order in the retreating army, and got most of the survivors back to Barcelona. When news of the defeat reached General Caldagues, the commander of the Spanish troops outside Barcelona, he abandoned the lines to the east of the city, and retreated to the western bank of the Llobregat, taking up a position at Molins de Rey. On the following morning St. Cyr entered Barcelona in triumph and the long siege was over. Four days later, on 21 December, he attacked the Spanish at Molins de Rey, forcing the last Spanish forces away from Barcelona.