Peninsular War

Spies And Sabres: How Wellington Won At Salamanca

A look at one notable example of how the British beat Napoleon's forces, making July 22 'Salamanca Day'.

Peninsular War

“Using… long messages to test frequency, it could be revealed that certain numbers – 2, 13, 210, 413 – appeared a lot more often than others.”

It was June 1812, and the numbers were part of a military encryption system devised by the French. 

Mark Urban reveals in the Guardian that the last part of this system was being painstakingly analysed one night that summer to tease out those parts which had so far remained elusive.

The eyes peering in the flickering candlelight belonged to Major George Scovell, an officer of the British army’s Intelligence Branch and codebreaker for Arthur Wellesley, aka the ‘Iron’ Duke of Wellington.

For the last several years, the British had been going around the Iberian Peninsula attempting to defeat Napoleon’s forces. He’d recently siphoned off a number of them to fight in Russia, but a vast army of 230,000 remained in the west, pitted against a mere 60,000 Brits, a 4:1 disadvantage.

Fortunately, diplomacy and espionage were areas where Wellington had the edge and alliances had allowed him to augment his force with Spanish and Portuguese fighters.

Whilst the French had blundered into the peninsula and relied on torturing locals for their intelligence, Wellington benefited from local sympathies and a vast network of spies.

One of these was Dr Patrick Curtis, aka Don Patricio Cortes, Rector of the Irish College in Salamanca, an institution founded years ago by those fleeing religious persecution back home. 

But centuries later alliances had changed. Now Curtis, the Irish Catholic and future Archbishop of Armagh, was onside with the Protestant King of Britain and Ireland, George III, against Napoleon. Whilst he dined with the French Emperor’s man in Spain, General Marmont, Curtis relayed vital intelligence gleaned from these conversations to George III’s man, Wellington.

Battle of Salamanca
The Irish College of Salamanca, where Curtis was based (image: Jose Luis)

Other intelligence came from local guerrillas who took letters from French officers and message carriers and passed them to Scovell. 

One of these was a letter dated July 9, 1812, from Napoleon’s brother Joseph (who he’d placed on the throne of Spain) to Marmont. According to Urban:

“The tiny dispatch had been written on a sliver of paper, most probably hidden in a riding crop.”

Now that it had been located, Scovell’s task was to deduce the remaining parts of cipher he didn’t yet know and reveal its message to Wellington.

By this point, code-making had been developing in Europe for about two-hundred years. In France, King Louis XIV had at his disposal a ‘Great Cipher’ of 600 numbers which, through conversion tables, converted whole words, word parts or single letters into numbers.

Before the battle of Salamanca, the French introduced a system like this that utilised 1,400 numbers – on the face of it, an uncrackable code.

But overconfidence in their system had led to complacency and correspondence was often not entirely encrypted. French commanders would often save time and effort by writing in French with only the most sensitive parts of their letters done in code. 

This meant that Scovell was able to piece together the coded portions of messages from the uncoded sections around them, using these portions to provide vital context.

As noted, number frequency was also a vital clue, with 2, 13, 210, 413 occurring most often. This eventually led Scovell to deduce that 210, for instance, was actually et, the French word for ‘and’. 

It had finally all come together, and now that it had there was no time to lose:

“This gave Wellington the last, vital piece of an intelligence jigsaw. He now knew exactly how many troops Marmont had, which neighbouring French commanders had declined to help him, and how soon the king would arrive with reinforcements. The British commander understood he had a window of opportunity to bring Marmont to a battle, and on July 22 (about two days before the decoded letter suggested French reinforcements would join his army and tip the scales) Wellington took [the opportunity to strike] at Salamanca.”

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A map of the peninsular campaign as it was in 1811 – Cuidad Rodrigo, shown in the circle, was captured by Wellington in 1812 and used as a base of operations (image from ‘Salamanca 1812’ by Ian Fletcher © Osprey Publishing, part of Bloomsbury Publishing)
Peninsular War
The road back from Salamanca to Ciudad Rodrigo (cities shown inside the circles) was an important factor the battle (image: Google)

At the end of June, with 48,000 of his men and 54 guns, Wellington drove Marmont’s army - smaller at that point by 4,000 men - out of the forts around Salamanca.

But this was just a prelude – the real battle would come in a few weeks.

From there, Marmont tried to outflank Wellington, marching his men south-east along the right bank of the Guarena river whilst Wellington marched his men down the left bank. Each side wearily kept an eye on the other, tiring out under the hot July sun.

Eventually, there was a fork at the Poreda, a tributary, sending Wellington’s men, who stuck to the left bank, towards the south-west. 

For a time, the triangular space between them was widening and opening up, but Marmont then crossed over the left bank of the Guarena. As Ian Fletcher explains in ‘Salamanca 1812’:

“This was the famous parallel march of 20 July, with Wellington’s army in three parallel columns, Marmont’s in two, each army watching and waiting for any signs of disorder among the other. The two armies got even closer when Marmont ordered his men to cross to the left bank of the Guarena to march south-west in the direction of Cantalpino.”

The whole episode seems bizarre by today’s standards: 

“It was one of the most memorable days of the Peninsular War, as the two great armies marched at speed, with parade ground precision, within a few hundred yards of each other. Thousands of tramping feet, and hundreds of wheels of the guns and wagons, kicked up huge clouds of dust which added to the stifling heat, and made for an uncomfortable if unforgettable march. Indeed, Marmont himself later said that he had never seen such a magnificent spectacle as the parallel march of two armies of over 40,000 men each at such close quarters.”

The French fired their canons at the British at the village of Cantalpino as the two armies paths were about to converge.

But Wellington coolly refused to return fire and veered south-west – he wasn’t ready to fight just yet.

The night before the battle there was a violent thunderstorm that disrupted the cavalry by disturbing the horses and sending dozens bolting into the darkness – several men were trampled to death in the chaos. 

This affected both sides but it came to be thought of as an omen of British victory, as a similar storm would happen before the Battle of Waterloo three years later.

The two armies eventually met just south of Salamanca on July 22, 1812, when Wellington moved to cut off the French advance. He had to move for fear of having his lines of communication running back to his stronghold at Ciudad Rodrigo, near the Portuguese-Spanish border, cut off.

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The march taken by both sides with the British shown in red and the French in blue (image from ‘Salamanca 1812’ by Ian Fletcher © Osprey Publishing, part of Bloomsbury Publishing)

Salamanca was to be Marmont’s first battle as commander in the Peninsula, though he had several experienced generals with him.

Wellington - who, at 43, was five years Marmont’s senior – was, conversely, lacking in experienced subordinates. 

One rather embarrassing reason for this is that one of his cavalry commanders and eloped with his sister-in-law a few years before. This surely hadn’t helped the reputation of the cavalry as being at this time a rather problematic arm, as Fletcher explains:

“The Allied cavalry gained a reputation for, as Wellington put it, ‘galloping at everything’, and had thus become something of a liability within the army. This uncontrolled urge to charge everything in their front on every occasion was demonstrated right up to the final battle of the Napoleonic Wars, Waterloo, on that occasion by the Union Brigade.”

At least at Salamanca, Wellington would have good cavalry leadership in the form of General Le Marchant, who was known as ‘a scientific soldier’ because of his extensive training and knowledge of his arm. His worth at Salamanca would be tragically proven. 

Wellington had also lost some talented subordinate commanders in prior battles, such as the assault on Ciudad Rodrigo, and in an attack on the stronghold of Badajoz, near the Portuguese border. 

This assault had been particularly frustrating and costly for the British and, in a manner that ran counter to the ‘hearts and minds’ campaign Wellington had otherwise been fighting and winning, they committed atrocities on the inhabitants when they finally broke inside. 

It’s worth remembering that, while the conduct of the British in the Napoleonic Wars displayed great military prowess and self-sacrifice, the total losses sustained during the Peninsular War paled in comparison to the Spanish. With around 60,000 men deployed at any one time, total British deaths over the six-year effort came to about 40,000, a staggering proportion by today’s standards to be sure. But the Spanish would lose one million people by 1814… from a population base of only 11 million.

It was precisely because of the ordinarily good relationship Wellington had with the peninsula’s indigenous population and its leaders that coordinated actions by local allies could be launched. These helped keep the French tied down so that Wellington could move against Marmont at this critical juncture in the war.


“The morning of 22 July dawned warm and sunny, which came as a welcome relief to the French and Allied troops after their soaking the previous night. The hot sun soon dried out the ground enough for clouds of dust to be kicked up by the two armies as they marched into position.”

‘Position’ initially meant lining up north to south, with the British facing west and the French east, with Marmont intending to turn the battle towards the south-west so he could cut across the British and along their line of retreat to Ciudad Rodrigo. In this way, he felt he could hem the British in against the Tormes river and Salamanca behind them.

Marmont had received word that the British baggage train had departed down the Ciudad Rodrigo Road (it had) and got the impression the rest of Wellington’s army must be on the backfoot and possibly following it (it wasn’t). Dust coming from the Allied – British, Spanish and Portugese - side was, in fact, the result of cavalry preparations. 

Contrary also to Marmont’s expectations was the fact that the battle was going to tilt not south-west but south-east. 

Battle of Salamanca
A map of the battlefield with Greater and Lesser Arapil both circled (image from ‘Salamanca 1812’ by Ian Fletcher © Osprey Publishing, part of Bloomsbury Publishing)

This is because two rises in the south of the battlefield, Lesser Arapil and Greater Arapil, would become key bits of terrain. 

At first, a portion of Wellington’s forces were arrayed only behind Lesser Arapil – he had thus far been unaware that Greater Arapil, further south, presented an even greater prize.

But he soon realised his error and the centre of the battle began to converge on this area.

This wasn’t the first fighting of the day. Troops on both sides had been deployed ahead of their main bodies in order to screen them and, with both sides getting nervous about how close they were getting to one another, sniping had taken place.

But at first the main initative was seized by Marmont, with his forces seizing Greater Arapil before Wellington’s Portuguese allies could.

Marmont could now look out from the crest of the hill over much of the battlefield and see the twin spires of Salamanca’s two cathedrals. In fact, from here, the only part of the battlefield he couldn’t see was the ground immediately behind Lesser Arapil, where Wellington had hidden some of his troops.

British Napoleonic Infantry Tactics
A common tactic during this era, particularly for Wellington, was to use a hill to screen a large body of troops (image from ‘British Napoleonic Infantry Tactics’ by Philip Haythornthwaite © Osprey Publishing, part of Bloomsbury Publishing)

Next, French skirmishers moved forward just in front of the village of Los Arapiles and this prompted a brief artillery duel. 

The French got the upper hand but foolishly pressed on too quickly, over extending themselves:

“The potentially disastrous manoeuvre was not lost on Wellington when he was told of it. The story of Wellington’s ‘Salamanca lunch’ is almost as well known as the outcome of the battle. While the Allied commander-in-chief was ‘stumping about and munching’ on a piece of cold chicken, an aide-de-camp suddenly came racing into the courtyard of the farm, and told him that the French were extending to their left… Wellington is often reported as throwing the leg of chicken over his shoulder before leaping on his horse to take a look… exclaiming either ‘By God! That will do!’, or ‘The devil they are! Give me the glass (telescope) quickly!’.”

What he saw through his ‘glass’ was a gap that had opened up between the French forces. 

Racing on horseback to Aldaea Tejada three miles to his rear, Wellington told his brother-in-law in command of 3 Division to send his troops forward against the exposed French opposite, then raced across to the commander of 5 Division to tell him to do the same.


Salamanca, with the cathedral spires Marmont would have seen clearly visible (Image: afloresm)

The French were still on the hills east of Los Arapiles when the British attacked. 

The redcoats came under French artillery fire as they advanced but fire would soon be going back the other way. 

When Marmont noticed, from atop Greater Arapil, the dangerous gap that had opened between his main force and those on his southern/left flank, he raced down the hill to tell General Thomieres, commander of the French left, to realign himself with the main body of the French army.

But a British shell suddenly crashed nearby, injuring the French commander in the arm and ribs. He was carried off the battlefield.

In a freak coincidence, not long afterwards, the French second-in-command was also then injured in the exact same way. Command passed, by 6pm, to General Clausel.

Ian Fletcher picks up the action back at Greater Arapil:

“At about 16.40, Leith's 5th Division, after enduring a prolonged period under fire from French artillery, began its attack on [the French] division [positioned] above the village of Los Arapiles… When [they] reached the crest of the heights they found [the French] drawn up in squares, probably due to the fact that they could see Le Marchant's cavalry advancing on Leith's right flank. In the ensuing contest the British firepower broke the squares and caused the French to break formation...”

(Infantry squares, where the men clumped together to form a mass of bristling bayonets and muskets, was the best defence against a cavalry charge because horses would refuse to attack them; they were less effective against enemy muskets fired in volleys from parallel lines and a positive disaster if caught by artillery).

Musket exchanges gave way to a British bayonet charge that dislodged the French from the ridge. But unfortunately, it wasn’t over yet:

“…pouring over the crest of the ridge, roaring like a burst of thunder, came every fleeing infantryman’s worse nightmare – enemy cavalry. What was worse, these cavalrymen, some 1,000 in all, were the men of Le Marchant’s heavy cavalry brigade, the 5th Dragoon Guards, with the 3rd and 4th Dragoons. They were armed with long, straight swords, capable of inflicting terrible wounds upon enemy infantry; nowhere was the power of the 1796-pattern heavy cavalry sword more clearly demonstrated than at Salamanca.”

Le Marchant had been waiting at the village of Las Torres, and knew he was meant to attack once 5 Division had attacked the French atop Greater Arapil:

“An almighty strugged ensued as the French defended themselves desperately with their muskets against the awesome British broadsword. Indeed, the French only gave way after some fierce fighting on the part of the dragoons who by now had lost all formation. Sadly, their devastating charge was to end in tragedy. Le Marchant, riding with just half a squadron of the 4th Dragoons, came up against the fugitives on the edge of the wood, one of whom levelled his musket and fired, killing Le Marchant.”

Peninsular War
5 Division attacking the French at around 4:40pm, towards the high ground east of Los Arapiles (image from ‘Salamanca 1812’ by Ian Fletcher © Osprey Publishing, part of Bloomsbury Publishing)

British forces moving south to attack the exposed left flank fared better than their comrades around Greater Arapil… at least at first.

Being screened from view for much of their advance by wooded hills, 3 Division were able to avoid coming under artillery fire as their comrades in 5 Division had.

They weren’t the first to make contact with the enemy though. Portuguese cavalry rode on ahead and, peering through the undergrowth, they saw the French left moving tangentially across their position, their flank completely exposed. 

They charged, slamming into the French, breaking up an entire battalion (around 850 men).

Moments later, 3 Division came storming out of the treeline, though the French commander was able to recover and ordered 20 guns to the top of the nearest hill. Very soon, lethal grape and round shot were tearing into the lines of 3 Division as they advanced.

But it wasn’t enough to slow the British attack and, with the continued help of the cavalry, the French were defeated here too, Thomieres being killed and his divisional artillery captured.

Entire French regiments were also utterly decimated – the 101 Ligne lost two thirds of its 1,500 men whilst the 62 Ligne lost 868 out of 1,123 men (the rear regiment lost ‘only’ 231 out of 1,743 men). 

Survivors were sent scrambling back towards their comrades at Greater Arapil, who, of course, were themselves being decimated.

Hilly terrain east of Los Arapiles (or Arapiles), near Salamanca – note that distant country is reputedly less forested now that it was then (map: Google)

As well as the battle was going for Wellington, adjacently to Greater Arapil, the British 4 Division was soon at risk of making the same mistake as the French.

They headed into the fray along with Portuguese allies but, as the attack slowed down and lost momentum they were now the ones who risked being exposed.

More Portuguese troops poured in to assist them but in the process, scaled a five-foot-tall rocky ledge near a hill top only to find French musketeers waiting behind it. We can but imagine the horrific results:

“Some 386 Portuguese were lost in just ten minutes in their brave attempt to support the 4th Division.”

4 Division was now struck on two sides and scurried back into the valley between Greater and Lesser Arapil.

There was now a gaping hole in the centre of Wellington’s line and General Clausal rushed to exploit it.

4 Division scrambled, forming an infantry square on the slopes of Lesser Arapil but French dragoons had sped up on them and managed to get inside it, wreaking havoc with their sabres as they raced around on horseback.

Wellington now rushed forward his reserves who went crashing into into Clausal’s force. The British and their allies sustained significant casualties but the French were eventually driven back and then off the summit of Greater Arapil, sniped at as they retreated by German troops (George III was not only King of the United Kingdom of Great Britain and Ireland but also Duke and prince-elector of Brunswich-Luneburg/Hanover – thus, the British army had some German soldiers at this time).

Fletcher picks up the action:

“Beyond the dark masses of fleeing Frenchmen could be seen clouds of dust through which burst Wellington’s triumphant divisions. Away to the west the 3rd and 5th Division drove forward with Bradford’s Portuguese and the 7th Division on their left. Squadrons of British and Portuguese cavalry hovered, gathering up surrendering enemy infantrymen and sabring any that resisted.”

But the French weren’t going down without a fight, Clausal having instructed his subordionate, Ferey, to assist his fleeing comrades in the rest of the infantry: 

“Ferey, [whose]… division [now] clung to the top of a ridge to the south-east of the Greater Arapil… constituted the last line of French resistance as the rest of the French army fell back towards him… Ferey was aided considerably by a fairly steep ridge which allowed those at the rear to fire over the heads of those in front, and so more firepower could be brought against the oncoming 6th Division of Wellington’s army.”

What followed was a truly colossal gunfight:

“Ferey formed seven of his battalions (around 6,000 men) into lines with a single square on each flank and when [the British] got to within 200 yards of the French position, Ferey gave the order to open fire. Scores of dusty red-coated British infantrymen fell as the [huge] weight of fire… crashed into them… men halted to load and fire and the two sides began a deadly duel of musketry… both sides trading volleys for the best part of an hour.”

As the light faded the scene was illuminated not just by musket flashes but also by small fires as scrubs were set alight by burning cartridge paper dropped on the ground in the frantic melee. One dreads to think of any wounded who may have been caught in these small blazes, as Mexican soldiers were in the opening battle of the Mexican-American War.

Eventually the Allies got the upper hand, the French breaking under the continued British musket fire, then pursued by the Portuguese. 

They were also hammered by British artillery when the guns were eventually brought up, a cannonball tearing Ferey himself in two.

Battle of Salamanca
The battlefield today (image: Panoramio and Dale Jackaman)

French soldiers bolted into the woodland behind the battlefield, Wellington’s exhausted troops too tired to pursue them. 

This wasn’t the intention. Wellington had wanted to use some of the Spanish troops, who might have been on hand to pursue them. 

But the commander in question, D’Espana, had “let his nerves get the better of him, had panicked and had withdrawn his force. Even worse was the fact that he had neglected to inform Wellington of this unauthorised move, rightly fearing the wrath of his commander. Therefore, instead of finding that the remains of the shattered French army were hemmed in against the left bank of the Tormes (river), an exasperated and furious Wellington discovered that they had simply marched across the bridge and through the fords to make good their escape.”

They had made good their escape for now. Despite this, in the immediate aftermath, the scorecard was still impressively in Wellington’s favour. He’d sustained 5,214 casualties, with 700 dead; the French, meanwhile, had taken 14,000 casualties.

In general, 1812 would bring mixed fortunes for Wellington, but his success at Salamanca would eventually, of course, be cemented by others, most notably Waterloo, making him the Marlborough of his era.

This was in no small part due to the espionage war being conducted behind the scenes. As Mark Urban reminds us:

“By late summer 1812, Scovell had cracked the code so comprehensively that there were few remaining areas of uncertainty. Wellington was able to plan his campaign of 1813 with a knowledge of the entire French scheme of operations. Scovell was rewarded for his work with two promotions in little over a year and, later, by a knighthood.

"In the early summer of 1813, armed with excellent intelligence, Wellington drove the French armies across northern Spain and defeated them at Vitoria. Joseph's kingdom collapsed after this further blow and he was recalled to France in disgrace. Until the end, he never suspected that the Great Cipher had been broken.”

For more on the battle and military history of the period, read ‘Salamanca 1812’ by Ian Fletcher, ‘British Napoleonic Infantry Tactics 1792-1815’ by Philip Haythornthwaite and visit Osprey Publishing for more military history. Read Mark Urban’s ‘The Man Who Broke Napoleon’s Codes’ for more on Major George Scovell.