The siege of San Sebastian (28 June-31 August 1813) saw Wellington successfully capture the last French stronghold on the northern coast of Spain, although after a longer siege than had been originally expected.
In the aftermath of the French defeat at Vitoria, they retreated back towards France, leaving garrisons in Pamplona and San Sebastian as they went. Wellington attempted to catch King Joseph and the main army around Pamplona, but by the time he arrived outside the city on 26 June, the French had escaped to the north. Wellington then spent another three days attempting to catch Clausel’s Army of Aragon, which was dangerously isolated in the Ebro valley, to Wellington’s south, but without success. This effort was cancelled on 29 June, and Wellington prepared to put his troops into a defensive posture facing the French border.
San Sebastian was a small town, but in a strong position. The town was built on a low sandy peninsula, dominated by the 400ft Monte Orgullo at its northern tip. The old castle of La Mota was on top of this mountain, and three gun batteries on the landwards face. To the west, north and east the mountain was protected by the sea and its steep slopes. In 1813 the town occupied the northern third of the peninsula. At the southern end was the monastery of San Bartolomé, built on a hill, and used by the French as an outlying fortress. The southern, land wall of San Sebastian was 400 yards wide, with demi-bastions at each end and one large bastion in the centre, and the standard arrangement of outworks, forming a powerful hornwork. The western front of the town was defended by the bay. The eastern front faced the River Urumea, which was tidal at this point, so at high tide the town was protected by a wide estuary but at low tide the river flowed down a narrow channel, and the estuary became sand and mud flats. The eastern side of the town was protected by a curtain wall, with one small bastion and two round towers.
The town was defended by 3,000 troops under General Emmanuel Rey, who was determined to put up a good fight. Throughout the siege he remained in contact with France by sea, as the Royal Navy was never able to put in place an effective blockade. This meant that news could get in and out of the town, supplies and reinforcements could get in, and the wounded get out. Rey began the siege with 3,185 men, and still had 2,996 by 15 August, despite having suffered 850 casualties in that period.
The siege began on 28 June, when four battalions of Biscayan volunteers began a blockade. On the same day they attempted to storm San Bartolomé, but were repulsed with heavy losses. On 3 July they were hit by a French attack, which forced them to retreat two miles
While Wellington moved east towards Pamplona, a smaller force under General Sir Thomas Graham was sent north to try and cut off Maucune’s retreat towards San Sebastian and Bayonne. When this attempt failed, Graham was put in charge of the siege of San Sebastian.
On 6 July Graham suggested replacing the Spanish irregulars with regular troops, and on 7 July the British 5th Division and Bradford’s Portuguese brigade took over the siege. The 5th Division took up a position facing the convent, while the Portuguese occupied the san hills of Chofre, east of the river. His siege guns were landed at Pasaia, two miles to the east, on 7 July. Graham had a total of forty heavy guns - 28 that had arrived by sea, six from the army reserve and six from HMS Surveillante.
Although General Sir Thomas Graham was put in charge of the siege, the plan of attack was drawn up after Wellington examined the walls from the east. He approved a plan put forward by Major Charles Smith, Graham’s chief engineer, for an attack across the river. The same time the fortified convent of San Bartolomé would have to be captured before the main attack, to allow a diversionary attack on the peninsula. This was based on an earlier siege, when the Duke of Berwick captured the town in 1719, but on that occasion the town’s governor surrendered the moment a breach had been created.
On 7 July Graham made his first attempt to capture the convent, using Portuguese 8-pounders to bombard it, but these weren’t powerful enough to damage the walls. Work on the proper siege batteries then began, with two facing the convent, three on the sand hills to the east and one on Monte Olia.
On 14 July a bombardment of the convent began. By the end of 15 July the roof and part of the walls had been destroyed, and that afternoon General Oswald sent the 8th Cacadores to attack the ruins. However the position was defended by two French battalions, and the attack was repulsed with the loss of 65 men. The bombardment began again on 16 July, and more damage was done. A second assault was launched at 10am on 17 July, with the equivalent of three battalions, again mainly Portuguese. This time the convent fell and its defenders fled into a nearby suburb. The French reserves counterattacked, but were in turn attacked by British troops from the 1/9th. The attackers pursued them towards the main walls, where they came under fire from the main fortifications and suffered heavy losses. By the end of the day the Allies had lost 207 killed and wounded, the French 40 dead and 200 wounded.
The fall of the convent allowed Graham’s engineers to build two new gun batteries on the same hill, and on 18 July the guns that had been used against the convent were moved into them. These two batteries were to be used to fire along the length of the sea wall. Two more batteries were built to their east, for use against the land wall, and two more batteries were added on sand hills.
The main bombardment began on 20 July, when nine of the eleven siege batteries opened fire. The bombardment began to damage the sea wall, but French counter battery fire knocked out five of the eleven guns in the largest of the batteries in the east. On 21 July Graham issued a demand to surrender, which Rey unsurprisingly turned down. The bombardment then resumed from 21-24 July, and a sizable breach was soon made. A second breach was made further to the north.
Graham had hoped to launch his first assault early on 24 July, but the bombardment had set the nearby parts of the town on fire, and so the attack had to be postponed until the following day. As a result the French were given more time to build fortifications behind the breaches. There was still a drop of 15-20 feet from the top of the breech to the street behind, and the French had fortified the ruined buildings facing the breach. The postponement also allowed the French to bring some of their remaining guns out of hiding and into places where they could protect the breach.
The assault was to be carried out by Major General Sir John Oswald’s 5th Division and Brigadier General Thomas Bradford’s Portuguese brigade. A mine had been dug under the hornwork on the land side, taking advantage of a water tunnel. This was to be blown as the signal for the start of the attack. If the mine blew down the scarp and counterscarp, then the Portuguese were to try and take the hornwork. The main attack was to be carried out by the 5th division. They had to emerge from a narrow trench, dash across the estuary, then move north in the gap between the walls and the river to reach the breach.
The mine was detonated at 5am, and caused more damage than expected. The Portuguese attacked, got into the ditch and attempted to break into the fortifications, but the attack hadn’t been well planned and was unsupported, as nobody had expected the mine to do so much damage. The attack was repulsed.
Despite the difficulties of crossing the estuary in the dark, the main assault part reached the breach and the leading troops reached the top of the breach, only to find a 20ft drop on the far side. The urgently needed ladders were some way down the column, and the attackers were unable to take advantage of their early success. The French then opened fire, and the leading part of the column suffered heavy losses. Another part of the column got confused in the dark and attacked into the gap between the main walls and the hornwork. This was a dead end, and the fighting here prevented reinforcements from reaching the real breach. After about half an hour the attackers were forced to retreat. The second wave of attacking troops were still trying to leave the narrow trench, and never got into the battle. This failed attack cost the attackers 571 casualties, including 330 from the Royal Scots, who had led the attack on the main breach and 138 from the Portuguese. The defenders lost 18 dead and 49 wounded.
This unsuccessful assault took place on the same day as the start of Soult’s counterattack, the battle of the Pyrenees. This was aimed at raising the siege of Pamplona, which was believed to be in more danger of being starved out, and only then moving to San Sebastian. However a diversionary attack was launched at Irun (25 July 1813), to the east of San Sebastian, to try and confuse Wellington. The French were successful at the passes of Maya and Roncesvalles, and Wellington was forced to move east to prevent them from lifting the siege of Pamplona. The French were held at Sorauren (28 and 30 July), and Soult was forced to retreat.
Wellington had visited San Sebastian in the aftermath of the failed assault on 25 July, and ordered the siege to continue, but when news arrived of the French attacks at Maya and Roncesvalles, he changed his mind. Graham was ordered to move most of his guns back onto the ships at Pasaia (known as Passage at the time), and move most of his men to defend the lower Bidassoa. Six guns were to be left in the batteries to try and hide these moves. The secret didn’t last for long. Rey suspected that something had happened, and on the night of 26-27 July launched a successful sortie against the parallel on the peninsula, capturing 201 men from Spry’s Portuguese brigade and damaging the siege works.
Soult’s offensive ended in defeat at the two battles of Sorauren. At the first battle of Sorauren (28 July 1813) his attempt to attack Wellington in a strong position on a ridge ended in inevitable failure. Soult then decided to try and slip away to the west to cut Wellington’s route back to San Sebastian, but his attempt to disengage ended as a costly retreat (second battle of Sorauren, 30 July 1813), and Soult was forced to retreat back towards France.
Wellington was thus free to concentrate on the siege of San Sebastian. The guns that had been put back on the ships at Pasaia began to be unloaded on 6 August. More guns were expected from Britain at any time, although contrary winds kept them pinned in harbour at Portsmouth until 27 July. The first of the guns began to reach Pasaia on 18 August, followed after five days by the first ammunition. Wellington decided not to resume the bombardment until the new guns were in place, so the French were given several weeks to repair what damage they could, and built new defences behind the breaches.
On the Allied side there was some debate about what to do next. On 7 August it was decided to repeat the first attack, but on a larger scale. More guns would be added to each of the breaching batteries, and an attempt would be made to expand the main breech so that it included part of the south wall as well as the eastern river wall.
Once the new guns had arrived, work began on constructing new gun batteries to hold them. When these were all complete Wellington had 48 guns on the sand hills east of the town and 15 to the south. The bombardment was resumed at 9am on 26 August. The main bombardment from the east was effective, but the batteries from the south turned out to be too far away from the walls, and new ones were built 250 yards from their targets. On the night of 27-28 August Rey launched a sortie against these new batteries, but it was repulsed. This new battery opened fire on 29 August. By the end of 30 August the bombardment had done its work. The main battery was now 300 yards long, and reached as far south as the hornwork. The northern beach was also expanded. This was still much smaller than the main breech, but it was believed that there was no second line of defences behind it.
General Graham planned to assault the walls at 11am on 31 August. The unusual daylight timing of the attack was forced on him by the tides, as he required low tide to expose the beaches. The main breech was to be attacked by the 5th Division, despite its failure in the first attack, along with Bradford’s Portuguese. 750 volunteers were raised from the 1st, 4th and Light Divisions, to help improve the morale of the 5th Division. When they arrived, the 5th Division refused to allow them to attack first, so they were allocated as a reserve. The northern breech was to be attacked by 800 volunteers.
The details of the attack were worked by General Sir James Leith, who had only just arrived from Britain to take command of the 5th Division. The main attack would be led by Robinson’s brigade. One column was to aim for the original breech on the right, while a second would attack at the left, where the bastion of San Juan had been badly damaged. It was hoped that these troops would be able to get onto the intact curtain walls, and thus get around the French second line. The Portuguese were to wade across the mouth of the river in an attempt to surprise the defenders.
At dawn on 31 August all of the British batteries opened fire, and kept up a heavy fire until 10.55. They then stopped, to allow the attack to begin. This preliminary bombardment caused very few casualties, but it did disable a massive mine that the French had dug under one of the towers, saving the attackers from suffering heavy losses.
The first attackers left their trenches at 10.55am, led by Lt Maguire of the 1/4th and a forlorn hope of twenty. Maguire reached the foot of the breach, where he was shot dead. At the same time a French mine near the Hornwork was fired, destroying a party of engineers that had been sent to try and disable it. Robinson’s men reached the head of the breach, where they came under heavy fire from the surviving French guns and the defenders of the second line. The attackers were faced with a 20ft drop down from the top of the breech into the town, and for half an hour were unable to make any progress, while suffering heavy losses. Eventually the attackers concentrated their efforts at the northern and southern ends of the breech, where narrow gaps existed that might allow a handful of men to pass. These attacks also failed, again with heavy costs. More attackers were thrown into the battle (including the volunteers), directed by General Leith, who took up a position on the beach outside the sea wall. With him was the chief engineer, Sir Richard Fletcher, who was shot and killed, and Leith’s predecessors Oswald, who was soon wounded. Leith remained at the front for two hours before he was hit by a shells splinter which broke his army and forced him to pull back.
At 11.35 the attack on the minor breech began. The Portuguese crossed 700 yards of beach and 200 yards of water in ten minutes, and the French gunners were only able to fire twice before they reached the walls. The Portuguese reached the walls by 11.45, but then got split in two, with half of their force attacking the minor breech and the other half joining the right hand flank of the attack on the main breech. The first attack on the minor breech failed, but the second one had more success, and the Portuguese reached the top, discovering that there was indeed no second line here. However the French were still able to hold the line for some time.
By 12.15 the attack on the main breech had effectively failed. The attackers had been forced to retreat back into cover on the outside of the breech, where they were still coming under fire from the flanks. Graham now made a daring decision, which changed the course of the battle. He ordered the guns on the sand hills to fire over the top of the attacks and hit the French defences. This bombardment lasted from 12.15-12.35, and the gunners were now so experienced at hitting their targets that hardly any of their shots fell short into the attackers. In contrast the French suffered very heavily as the bombardment hit fully manned defences.
When this bombardment ended, the attackers got back to their feet, and finally managed to make progress on the left, eventually capturing the eastern end of the high curtain wall on the land front. This meant that the Hornwork was now exposed to attack, and the defenders retreated into the town. The attackers had also got around the southern end of the second line of defences, and were able to get into the town behind it. At the other end of the breech the volunteers from the Light Division also got into the town. Finally, at about 1pm one of the French magazines blew up, killing many of the defenders in that part of the town. After some hard fighting the French were forced back from the southern walls. At the same time the troops on the right of the main breech had pushed north and forced the French away from the minor breech. By 1.35 French prisoners were being collected and taken out of the town, and by 2.15 the French had been pushed back to the Mirador, at the eastern end of the castle rock. The town had finally fallen to Wellington’s men,
Rey managed to retreat back into the castle with 1,000 men, giving him a garrison of 1,300 men. If it had been possible to organise a full scale assault on the castle immediately, it might well have fallen quickly, but by now the town was on fire, all but one of the senior British officers involved had been wounded, and the weather turned and a storm began, which lasted for the rest of the day. At the same time many of the British soldiers settled into yet another sack of a captured Spanish town. As a result the French were able to hold onto the castle.
The attacking troops had suffered very heavy losses, with Robinson’s brigade losing 20 officers and 312 men killed and 28 officers and 502 men wounded out of a total of 1,500, while the overall casualties were around 664 killed and 1,047 wounded.
While one part of Wellington’s army was storming San Sebastian, another part was defeating Soult’s last attempt to save the town, an attack on the coastal front that was repulsed at the second battle of San Marcial.
Wellington was still faced with the problem of how to force General Rey to surrender. He had 1,300 fit men, 450 wounded and 350 prisoners from the fighting on 25 July and 27 July in the castle. He had four heavy guns, four light guns and three mortars left from the thirty one guns that had been on the hill before the bombardment. There was very little cover on the hill, and only the cellars below the castle could be considered secure.
On 1-3 August Wellington’s gunners bombarded the castle. On 3 September Graham issued a summons to surrender, which Rey turned down. Wellington then ordered work to begin on regular siege works, heading towards the castle, including two large gun batteries. By 8 September Wellington opened fire with 61 guns and mortars. After only two hours Rey surrendered, well aware that his magazine in the castle could be hit and detonated at any time. The defenders were allowed to march out with the honours of war, and their women and children allowed to return to France.
Once again Wellington’s engineers had mismanaged a siege. In an attempt to avoid a formal attack on the southern walls of the town, they selected a line of attack that looked to be easier but was actually more difficult, and probably at least doubled the length of the siege. Even so, the town fell before Wellington was actually ready to resume his offensive, as he continued to wait for news from Germany.