Twelfth Siege of Gibraltar The Twelfth Siege of Gibraltar was fought between September 1704 and May 1705 during the War of the Spanish Succession . It followed the capture in August 1704 of the fortified town of Gibraltar , at the southern tip of Spain , by a Anglo – Dutch naval force led by Sir George Rooke and Prince George of Hesse - Darmstadt . The members of the Grand Alliance , Holy Roman Empire , England , the Netherlands , Pro - Habsburg Spain , Portugal and the Savoy , had allied to prevent the unification of the French and Spanish thrones by supporting the claim of the Habsburg pretender Archduke Charles VI of Austria as Charles III of Spain . They were opposed by the rival claimant , the Bourbon Philip , Duke of Anjou , ruling as Philip V of Spain , and his patron and ally , Louis XIV of France . The war began in northern Europe and was largely contained there until 1703 , when Portugal joined the confederate powers . From then , English naval attentions were focused on mounting a campaign in the Mediterranean to distract the French navy and disrupt French and Bourbon Spanish shipping or capture a port for use as a naval base . The capture of Gibraltar was the outcome of that initial stage of the Mediterranean campaign . At the start of the siege , Gibraltar was garrisoned by around 2 , 000 Dutch , English , Austrian and pro - Habsburg Spanish troops facing a besieging force of up to 8 , 000 French , pro - Bourbon Spanish and Irish troops . The defenders were able to hold off the numerically superior besieging force through exploiting Gibraltar ' s geography and the small town ' s fortifications , though they were frequently short of manpower and ammunition . The besiegers were undermined by disputes between the French and Spanish officers and terrible conditions in their trenches and bastions , which led to outbreaks of epidemic disease and undermined morale . Sea power proved crucial , as the French navy sought unsuccessfully to prevent the Grand Alliance shipping in fresh troops , ammunition and food . Three naval battles were fought during the siege , two of which were clear defeats for the French and the last of which resulted in the siege being abandoned as hopeless after nine months of fruitless shelling . The outcome was disastrous for the French and Bourbon Spanish side , which was said to have lost 10 , 000 men against only 400 for the Grand Alliance . Aftermath of the capture of Gibraltar . The loss of Gibraltar in August 1704 was a humiliation for Philip V of Spain and posed a real strategic threat to his rule . It was not only , as a later Spanish writer put it , " the first town in Spain to be dismembered from the domination of King Philip and forced to recognise Charles , " but it also potentially had great value as an entry point for the Grand Alliance armies . Its possibilities were recognised immediately by the Alliance forces ' leader Prince George of Hesse - Darmstadt , who told Charles in a letter of September 1704 that Gibraltar was " a door through which to enter Spain " . An army landed at Gibraltar could advance rapidly along the coast to Cadiz , supported by naval forces , and capture the port . From there it was a relatively short distance to Seville , where Charles could be proclaimed king , following which the Alliance could march to Madrid and finish the war . Gibraltar itself had been largely emptied of its population , most of whom left the town after its capture and had moved to temporary accommodation elsewhere in the Campo de Gibraltar . Only a few dozen Spaniards and a small community of neutral Genoese remained . The town was garrisoned by a motley assortment of Alliance forces , consisting of around 2 , 000 British and Dutch marines , 60 gunners and a few hundred Spanish , mostly Catalan , followers of Charles of Austria . They were supported by Sir George Rooke ' s Anglo - Dutch fleet consisting of 51 ships of the line operating in the Strait of Gibraltar . The Alliance had two significant disadvantages – limited supplies and a pressing need for their ships , which had already been at sea for six months , to be repaired and reprovisioned . As soon as Gibraltar was captured , the Alliance set about preparing for a Two Crowns counter - attack . The Alliance fleet sailed a short distance across the strait to Tetuan in Morocco , where it took on fresh water . On 22 August , a French fleet was sighted in the strait but began to withdraw after being spotted . Rooke caught up with the French off Málaga on 24 August and attacked , in a bid to prevent the French from slipping past him and attacking Gibraltar . The two fleets were evenly matched but the French ships were faster and had more ammunition than the confederates . They did not manage to make this advantage count , however , and the Battle of Vélez - Málaga was effectively fought to a draw . No ships were sunk but both fleets took very heavy casualties with around 3 , 000 killed or wounded on each side , including the French commander . The Anglo - Dutch fleet was hampered by a shortage of shot and gunpowder , much of which had already been used in bombarding Gibraltar during the operation to capture it , and Sir George Byng ' s squadron was forced to pull back when it ran out of ammunition . The rest of the fleet was dangerously low on ammunition but fortunately for the confederates , the French withdrew the following day , leaving the Anglo - Dutch fleet to limp back to Gibraltar . Having dealt with the French naval threat , Rooke left as many men , guns and supplies at Gibraltar as he could before sailing for home . He split off part of his fleet , leaving Admiral Sir John Leake with 18 ships to patrol the strait and the Portuguese coast . The Spanish had already mobilised their forces and at the start of September the Marquis of Villadarias , the captain - general of Andalusia , arrived in the vicinity of Gibraltar with an army of 4 , 000 men . Villadarias planned to increase his force to 12 , 000 , consisting of 9 , 000 Spaniards and 3 , 000 Frenchmen . The Two Crowns force was also supplemented by many of the civilian refugees from Gibraltar . Start of the siege . Hesse set about improving Gibraltar ' s defences to make it as difficult as possible for the enemy to mount a frontal attack . The town is set on the western side of a rocky peninsula connected to the Spanish mainland by a narrow sandy isthmus . The north side of the Rock of Gibraltar presents a vertical cliff ; the only access to the town was via a narrow strip , only about wide , which was blocked by the heavily fortified curtain wall known as the " Muralla de San Bernardo " ( later the Grand Battery ) . The prince sought to reduce this strip even further by flooding it , forcing any attackers to use a narrow path between the Rock and the inundated area or to advance along the narrow shoreline . He set up cannon in five batteries along the north side of Gibraltar : on the Old Mole , to provide flanking fire from the west ; on the " Baluarte de San Pablo " ( later North Bastion ) and on the Landport curtain walls , to provide direct fire onto the isthmus ; on the " Baluarte de San Pedro " ( later Hesse ' s Demi Bastion ) , to provide flanking fire from the east ; and in a Round Tower , on a clifftop spur overlooking the isthmus ( later the site of Forbes ' Batteries ) , from where fire could be directed onto enemy troops on the far side of the inundated area . A " bomb ship " was also installed off the Old Mole , carrying a heavy mortar to provide additional flanking fire from the west . Although Hesse was confident that he would be able to hold Gibraltar against the numerically superior Franco - Spanish force , he was undermined by political disputes between the Habsburg and English commanders . There was widespread resentment among the English marines that they had not been allowed to return with Rooke ' s fleet . There was a particularly poisonous relationship between the English Colonel of Marines Edward Fox and the Irish Colonel Henry Nugent , whom Hesse had appointed as Governor of Gibraltar . The two men had fought on opposite sides during the Irish campaign of William III ; the Protestant Fox had gone on to serve Queen Anne , while the Catholic Nugent had joined the service of Charles of Austria . Hesse wrote that Fox was " furious at being under my orders and at not being allowed to leave for England . His respect for the Governor I have appointed is even less . There is confusion everywhere . Orders are not carried out , and the officers are the first to make trouble . . . " The besieging French and Spanish forces were reinforced on 4 October when 19 French warships " great and small of the line of battle " escorted troop ships carrying 3 , 000 men with heavy guns and supplies of ammunition to a landing point near the ruined Roman town of Carteia at the head of the Bay of Gibraltar . This brought the number of soldiers under Villadarias ' s command to some 7 , 000 , which Hesse estimated consisted of eight Spanish and six French battalions of foot plus nine cavalry squadrons . Most of the French ships left on 24 October , to the surprise of the defenders , though six remained behind to blockade Gibraltar . After the reinforcements had settled in , the Spanish began digging siege lines and trenches towards the confederate positions . The first attack came on 26 October when Spanish guns opened fire on the confederate defences around the Round Tower , causing considerable damage . A French force carried out a simultaneous raid of Gibraltar ' s harbour , burning the bomb ship . Villadarias then carried out a heavy bombardment of the San Pablo bastion using 27 guns and 16 mortars , which managed to breach it . Among the casualties were the two feuding colonels , Fox and Nugent , who were killed on successive days . At the same time , an epidemic disease broke out among the Gibraltar garrison , reducing their effective numbers to about 1 , 300 men . The position of the garrison looked increasingly precarious . Hesse sent a message to Admiral Leake at Lisbon requesting his urgent assistance after the appearance of French ships in the bay . After receiving the message on 21 October , Leake set sail at once , bringing more supplies for the defenders . In the meantime , Hesse had to deal with an internal threat – a plot by some Habsburg Spanish officers , aided by some clergymen and British officers , to betray the garrison . He wrote to Charles in mid - October to inform the Archduke of what had happened : Charles wrote back advising Hesse to carry out a court - martial with independent judges to avoid any suspicion of prejudice . As the accused were Habsburg subjects , a court - martial consisting of British and Dutch officers – who did not owe allegiance to Charles – was convened to adjudicate the case . The British officers who were implicated in the plot appear to have been sent back to England ; their fate is not recorded . Gonzalez was convicted and on 23 February 1705 , " being guilty of high treason [ he ] was shot in the face of the whole garrison . " Assault on the east side . The Bourbon Spanish , meanwhile , were planning to carry out a surprise attack . Simón Susarte , a Spanish goatherd who had fled Gibraltar after its capture by Rooke a few months earlier , told Villadarias that there was a secret route by which the east side of the Rock of Gibraltar could be scaled . It required a climb of around , of which the upper section was near - vertical , but was passable with the use of rope and ladders via the Great Sand Dune . As the east side was considered virtually impregnable , only the west side was fortified ; if the Rock could be climbed from the east , an attacker could evade the fortifications and descend directly into the town . The route was reconnoitred and found to be passable by a lightly armed force . Villadarias decided to send a force of 2 , 000 men – nearly a third of his entire army – divided into two groups : an initial force of 500 to seize the heights at night , followed by a further 1 , 500 the following daybreak . The first 500 set off at dusk on 11 November , led by a Colonel Figueroa and guided by Simón Susarte . They made it to the top of the Rock , reaching its southernmost peak near where O ' Hara ' s Battery stands today , and descended part - way down the west side where they sheltered overnight in St . Michael ' s Cave . At daybreak they climbed the Philip II Wall , which extends up the west side of the Rock , and killed the English sentries in the lookout point at Middle Hill . A drummer boy bringing food to the lookout saw the invaders and raised the alarm . Hesse had anticipated some kind of attack from the rear and had kept a mobile force in reserve to guard against such an eventuality . It was formed by an English company , and two Spanish companies : a regular company under captain Francisco de Sandoval and a Catalan company of miquelets under Jaume Burguy , numbering 300 men , all of them led by Hesse ' s brother Heinrich . This reserve immediately responded and engaged the Spanish Bourbons at Middle Hill . Although the Bourbons had the advantage of height , they were effectively trapped against the precipice of the Rock and only had three rounds of ammunition each , as a result of travelling light ; they had not come prepared for a pitched battle . The Spanish Habsburg force led by Captain Burguy , made up of miquelets and regulars , marched ahead and dislodged the Spanish Bourbon grenadiers from the top of the hill . At the same time , Sandoval , with his remaining regulars and miquelets , charged upon the bulk of the assaulting force from one flank , while Heinrich von Hesse attacked from the other side . Around a hundred of the Bourbon force , including their colonel , were captured . Hundreds more were killed , either by defending fire or by falling off the Rock while attempting to flee . Only a few , including Simón Susarte , made it back to the Bourbon lines . The English subsequently ensured that there would be no repeat of this episode by blasting away the path used by the Spanish . The other 1 , 500 members of the Spanish force did not even set off to support the attack because , after the first 500 had left , Admiral Leake ' s squadron was sighted entering the bay with 20 ships . In the subsequent naval engagement , six French frigates were destroyed and a seventh ship was captured intact . Villadarias had apparently intended to carry out a multi - pronged attack but Leake ' s timely arrival meant that it fell apart . The French naval support for an assault on the moles evaporated , and a frontal assault via the isthmus – reinforced with the 1 , 500 men originally earmarked for the climb on the eastern side – failed entirely . Hesse ' s relief at Leake ' s timely arrival was evident in the letter that he sent the admiral after the battle , thanking him for turning up just as " the enemy were attacking us that very night of your entrance in many places at once with a great number of men . " Leake had not brought many supplies to Gibraltar but provided what he could , and loaned Hesse the fleet ' s skilled manpower , of which the confederate garrison was desperately short . A labour force of some 500 men was assembled from the ships ' companies and was put to work repairing the fortifications , remounting guns dislodged by Spanish fire and hauling cannon up the Rock to increase the fire being directed onto the Spanish batteries . One of those involved , Captain Willis , played such a prominent role that the track he used was renamed ( and is still known as ) Willis ' Road , and he also gave his name to Willis ' Battery ( now Princess Royal ' s Battery ) , Magazine and Guard . The siege settled down into a routine of bombardment and counter - bombardment . This proved increasingly trying for the defenders , who were running short of manpower , ammunition and supplies . Captain Joseph Bennett , an engineer whom Leake had brought with him , helped to bolster the fortifications but earned the wrath of some in the garrison , who felt that Gibraltar should be abandoned . He wrote to a friend on 6 December to tell him that " many officers had a design to quit the place and blow up the works but I always opposed them , and mentioned the garrison could be kept with the number of 900 men we had , and no more , as I believe you will have an [ account ] of . Some was for cuting " ( sic ) " my Throat and others for cuting " ( sic ) " off my Ears & c . " Many members of the garrison tried to sneak aboard Leake ' s ships to escape the siege . The situation was precarious and was only worsened when a storm damaged many of Leake ' s ships on 4 – 5 December . By this time , the garrison was critically short of medicines and supplies . Many were sick or injured and too few remained to carry out repairs to the shell - damaged fortifications . Only 1 , 300 were healthy enough to man the defences . Their living conditions were increasingly grim ; their shoes had worn out and many men wore makeshift sandals made from hay and straw . Reinforcements and the end of the siege . A few days later , Leake received the news that a convoy of 20 transport ships carrying supplies and reinforcements was on its way from Lisbon , escorted by four men - of - war . Adverse winds and currents meant that he was unable to sail to assist it against a French naval force that had left Cadiz , and he was forced to wait to see if the convoy would reach its destination . On 18 December , nine of the transports reached the bay , accompanied by two men - of - war , with another seven arriving on 20 December . Four were missing , having been intercepted by the French ; three of them had been sunk or captured while the last one eventually made it to Gibraltar at the end of December . They brought with them 2 , 200 men from the Grenadier Guards , Donegal ' s Foot and Barrymore ' s Foot , plus some Dutch troops , guns and supplies of powder , tools and food . Further reinforcements arrived between 16 – 18 January . With Gibraltar safe for the moment , Leake left for Lisbon on 3 January with sick and wounded members of the garrison aboard his ships . The Bourbon Spanish and French land force continued to bombard Gibraltar , inflicting further damage on the town ' s somewhat weak fortifications but were unable to make any progress against the reinforced garrison . They were being vigorously opposed with counter - bombardments , which killed many of their number , and by sallies , two of which were carried out successfully by the confederates on 23 and 31 December . Relations steadily worsened between the Spanish and French components of the besieging force , a trend that was exacerbated by the lack of progress they were making , the appalling conditions they were enduring in the open and the steady stream of casualties being caused by the counter - bombardment and outbreaks of epidemic disease . The weather , too , was terrible , with storms and heavy rain making life a misery . By the New Year of 1705 , the besieging force was disintegrating and had dropped in numbers from around 7 , 000 men to only 4 , 000 , the remainder having either become casualties or simply deserting . The situation was sufficiently alarming that King Louis XIV of France despatched Marshal René de Froulay de Tessé along with 4 , 500 French and Irish reinforcements to recover the situation . Villadarias , however , was determined to make one more effort to take Gibraltar before Tessé arrived . On 7 February , he sent 1 , 500 French , Spanish and Irish troops to seize the Round Tower , an outlying fortification on the cliff face above the present Laguna Estate . The attackers captured the tower but a confederate counter - attack drove them out , leaving 200 of them dead . The Spanish accused the French of fleeing the battlefield and leaving their flank unprotected . Tessé arrived in mid - February but was appalled to find how badly the siege was being run . His criticism of the Spanish officers led some to quit the siege in the face of what they saw as his insults . Their morale improved somewhat when Admiral Bernard Desjean , Baron de Pointis sailed into the bay on 26 February with a force of 18 men - of - war from Cadiz . Gibraltar ' s garrison immediately went on alert , expecting a landing at the south end of the peninsula , but this did not materialise . The reason soon became clear ; Leake had returned with a combined English , Dutch and Portuguese force of 35 ships . In the subsequent battle in the Strait of Gibraltar , the French lost five of their ships , including Pointis ' flagship , and Pointis himself was fatally wounded . Leake ' s fleet sailed into the bay on 31 March , bringing with it fresh troops from Mountjoy ' s Grenadiers and units of the Portuguese army . Hesse rejoiced at the admiral ' s arrival : Leake ' s arrival was " the final stroke " , as the French abandoned the siege as hopeless following an order from Louis XIV on 12 April . Tessé wrote bitterly to the king to blame the Spanish , telling him that " we have failed before Gibraltar for want of method and planning . . . the ill - fate of your vessels was due to lack of competence at Madrid . . . " With the French having gone home , Villadarias resumed command and began to convert the siege into a blockade by pulling back from the isthmus and removing his cannon . On 2 May , an Alliance scouting party found that the Spanish trenches had been abandoned . Later that day , Hesse accompanied a demolition party to destroy the Bourbon Spanish works , but some members of the party ventured out too far and were captured or killed by the Spanish cavalry . The following day , a larger party , protected by grenadiers , resumed the work of demolishing the Spanish batteries without further opposition , marking the end of the siege .