Battle of Diamond Rock The Battle of Diamond Rock took place between 31 May and 2 June 1805 during the Napoleonic Wars . It was an attempt by Franco - Spanish force despatched under Captain Julien Cosmao to retake Diamond Rock , at the entrance to the bay leading to Fort - de - France , from the British forces that had occupied it over a year before . The French in Martinique had been unable to oust the defenders from the strategically important rock , and the British garrison was able to control access to Fort - de - France Bay , firing on ships attempting to enter it with guns they had placed on the cliffs . The arrival of a large combined Franco - Spanish fleet in May changed the strategic situation . The French commander , Pierre de Villeneuve had orders to attack British possessions in the Caribbean , but instead waited at Martinique for clearer instructions . He was finally persuaded to authorise an assault on the British position , and a Franco - Spanish flotilla was despatched to storm the rock . Already short of water , the defenders held on in the summit for several days , while the French , who had forgotten to bring scaling ladders , could make little headway . The British , short of both water and ammunition , eventually negotiated the surrender of the rock after several days under fire . The British commander was subsequently tried by court martial for loss of his ' ship ' after repatriation , but was honourably acquitted . Background . Diamond Rock is fortified . Diamond Rock had been fortified in January 1804 on the orders of Commodore Samuel Hood . Hood had been active in the West Indies , protecting British convoys from French privateer s issuing out of the two major naval bases the French retained in the Caribbean , at Guadeloupe and Martinique . The privateers had captured a number of valuable cargoes and were diverting British warships to protect the merchant fleets . Hood decided to blockade Martinique , and thus curtail the privateers and intercept supplies destined for the French garrison . Patrolling off the bay at the southern end of the island , in which one of Martinique ' s two main ports , Fort - de - France , was located , Hood saw that if Diamond Rock could be occupied , it would allow the British to effectively control the shipping approaching the ports on the western side , as the currents around the island made the easiest approaches mean passing within sight of Diamond Rock . Hood reconnoitered Diamond Rock and considered it excellently defensible , with the only possible landing site being on the western side . He wrote that ' thirty riflemen will keep the hill against ten thousand . . . it is a perfect naval post . ' A party of men were landed on 7 January 1804 , from Hood ' s flagship , under the command of " Centaur " s first lieutenant James Wilkes Maurice . They promptly fortified the small cove they had landed at with their launch ' s 24 pounder , and established forges and artificers ' workshops in a cave at the base of the rock . After fixing ladders and ropes to scale the sheer sides of the rock , they were able to access the summit and began to establish messes and sleeping areas in a number of small caves . Bats were driven out by burning bales of hay , and a space was cleared by blasting at the top of the rock in order to establish a battery . In February a number of guns were transferred over from " Centaur " , with two 24 pounders being installed in a cave near sea level , another 24 pounder halfway up the rock , and two 18 pounders in the battery at the top . In addition to this the men had use of a number of boats , with one armed with a 24 pounder carronade , which were used to intercept enemy ships . Marshall ' s " Naval Biography " , when describing the process of hauling the guns to the summit , recorded that French reactions . Despite the vulnerability of both " Centaur " and the Rock to a French gunboat attack while the process of fortification was being carried out , the French neglected to act . The governor of Martinique , Louis Thomas Villaret de Joyeuse ordered work to begin on building a road to the coast opposite the rock , and the establishment of a battery there , but the British were forewarned by the black population of the island who were largely sympathetic to the British . A party was sent onshore , which succeeded in capturing the engineer sent to construct the battery , and three of his men . Work on the battery was abandoned after further British raids on the area . HM " Fort Diamond " . By early February the guns had been installed and tested . The 18 pounders were able to completely command the passage between the rock and the island , forcing ships to avoid the channel . The winds and currents meant that these ships were then unable to enter the bay . With work complete by 7 February Hood decided to formalise the administration of the island , and wrote to the Admiralty , announcing that he had commissioned the rock as a sloop , under the name " Fort Diamond " . Lieutenant Maurice , who had impressed Hood with his efforts while establishing the position , was rewarded by being made commander . Diamond Rock was to be considered a captured enemy ship , and was technically treated as a tender to one of the boats stationed there , commissioned by the Admiralty as the sloop " Diamond Rock " , superseding Hood ' s use of " Fort Diamond " . This was a mere technicality , and when the boat fell into French hands , another replaced it , and in time the rock became known as the ' Sloop Diamond Rock ' . The batteries were also named , the two 18 pounders at the summit were known as ' Fort Diamond ' or ' Diamond Battery ' , while the 24 pounder half way up was known as ' Hood ' s Battery ' . Life on the Rock . Maurice had a party of around 100 men under his command on the rock , with the usual officers found on a British warship , including a surgeon , purser , and a junior lieutenant to command the small supply vessel . A hospital was established , and food , gunpowder and ammunition were brought to the rock in boats , at first from " Centaur " , and then from Martinique , where it was purchased from sympathetic inhabitants . Water also had to be brought from the island , and large cisterns were built to store it . The men on the rock also ran the risk of falling from the heights or being bitten by the fer - de - lance , a poisonous snake inhabiting the rock . First French assault . With the British presence on Diamond Rock firmly established , Hood departed with " Centaur " , and the French saw an opportunity to attack . Four boatloads of soldiers were despatched at night , though the sailors who rowed there were extremely pessimistic as to their chances . Exhausted by the time they arrived at the rock , the men were not able to resist the pull of the strong current and were swept out to sea . They were eventually able to make it back to Martinique , with the British only learning of the attempt several days later . They could have easily sunk the French boats had they made a daylight assault , and disheartened by this failure , no further attempts were made to attack the fort from the island . Maurice and his men devoted their time after this to raiding and cutting out ships from the Martinique coast , and interdicting trade . Villeneuve arrives . On 14 May 1805 , seventeen months after the British occupied the island , a large French fleet arrived in Fort - de - France Bay , having briefly exchanged fire with the British on Diamond Rock as they did so . The fleet , under Pierre de Villeneuve , was joined over the next few days by Spanish ships under Federico Gravina . As the Spanish ship " San Rafael " approached on 16 May , the British hoisted the French flag , luring the Spanish ship to pass close by . As she did so the British forces replaced the French colours with the British , and opened fire , taking the Spanish by surprise . Shortly after this it was discovered that the main cistern , holding a month ' s supply of water , had cracked in some earth tremors , and the leak had been made worse by the vibration from the guns . There was barely two weeks left , but fresh supplies were now unobtainable as a blockade of the rock began by a number of schooners , brigs and frigates . The combined fleet carried a large number of soldiers , intended by Napoleon to be used to attack British possession in the Caribbean . Villeneuve felt however that his orders were not clear , and remained at Fort - de - France , hoping to be joined by a fleet under Honoré Ganteaume , which unbeknownst to him had been unable to break the blockade of Brest . For two weeks Villeneuve lingered in the bay , until finally being persuaded by Villaret de Joyeuse to use his forces to capture Diamond Rock , a thorn in his side for the past seventeen months . Villeneuve gave Captain Julien Cosmao of the 74 - gun " Pluton " command of the expedition . He was to take his ship , the 74 - gun , the 36 - gun " Sirène " , a corvette , schooner , eleven gunboat s , and between three and four hundred men , and retake the rock . Battle . The flotilla left their anchorage on 29 May , but were not able to work into a position to attack windward of the rock until 31 May . Lieutenant Maurice assessed the overwhelming strength of the French , and having decided that it would be impossible to hold the lower stages , spiked the guns covering the landing stage , scuttled the launch , and withdrew his forces to defend the upper levels . Four Spanish gunboats from the ships " San Rafael " , " Argonauta " , " España " and " Firme " participated in the attack , with a Spanish gunboat being the first to disembark troops on the rock under fire from the British positions . Cosmao began an intense bombardment while the infantry forced their way onto the landing stage , losing three gunboats and two rowing boats full of soldiers as they did so . The attacking force had however neglected to bring any scaling ladders , and could not assault the sheer rock sides . Instead they were forced to besiege the British forces in the upper levels . By 2 June , with his ammunition almost exhausted and water supplies running critically short , Maurice opened negotiations . At four o ' clock that afternoon flag of truce was displayed and a senior French officer was despatched in a schooner to offer terms . By 5 Maurice had agreed to surrender Diamond Rock , the officers were to retain their swords and the men would remain under their orders . They were to be taken to Fort - de - France , and from there repatriated to a British settlement at the first opportunity . With these terms agreed , the British surrendered Diamond Rock . The British had two men killed and one man wounded in the battle . French casualties were harder to judge , Maurice estimated they amounted to seventy , the French commander of the landing force made a ' hasty calculation ' of fifty . In addition to this the British had sunk five large boats , and potentially inflicted further casualties during the bombardment of the French warships . Maurice and his men were taken off the rock on the morning of 6 June and put on board the " Pluton " and " Berwick " . Aftermath . Maurice was returned to Barbados by 6 June , and sent a letter , dated that day to Horatio Nelson , who had recently arrived in the Caribbean in search of Villeneuve ' s fleet . Naval procedure at the time was that all commanders who lost their ships automatically faced a court martial . Accordingly , Maurice was tried by a court martial convened aboard the 28 - gun in Carlisle Bay on 24 June . Maurice was honourably acquitted for the loss , the verdict noting Villeneuve had retaken the rock , but the day the attack began the frigate had arrived with orders from Napoleon . Villeneuve was ordered to take his force and attack British possessions , before returning in force to Europe , hopefully having in the meantime been joined by Ganteaume ' s fleet . but by now his supplies were so low that he could attempt little more than harassing some of the smaller British islands . Anti - French feelings grew by the Spanish commander Don Federico Gravina after the capture of the Diamond Rock . Gravina wanted to invade the island of Trinidad as the British captured it from the Spanish a couple of years before . Villeneuve left Fort - de - France on 5 June , and on 7 June two French frigates sighted a convoy of 16 British merchants , and Villeneuve signalled general chase . The Spanish 80 gun ship of the line Argonauta and the two frigates chased down and captured 15 of the 16 merchants . The convoy was laden with sugar , rum , coffee , cotton and other products . From them he learnt that Nelson had arrived in the West Indies , in hot pursuit of Villeneuve . Shocked , Villeneuve abandoned his plans to raid the British colonies and immediately began preparations for the return voyage . The fleet got under - way on 11 June , causing one of the army officers attached to the fleet , General Honoré Charles Reille to note We have been masters of the sea for three weeks with a landing force of 7000 to 8000 men and have not been able to attack a single island . The capture of Diamond Rock and the seizing of 15 merchant ships were the only successes that the combined fleet had during their Caribbean campaign . The rock remained in French hands until the capture of Martinique in 1809 . The portraits mentioned under ‘ Battle ’ are part of a set of engravings published in Britain in 1805 . They were the work of John Eckstein , a German born artist who had lived in Britain and was now in the Caribbean using his neutral nationality to work on prisoner exchange . He spent a month on the Rock soon after it was occupied . The etchings set consists of a dozen coloured prints , the sheet of portraits of those involved and a frontispiece . Eckstein also wrote a substantial article for the Naval Chronicle on his experiences in which he expressed his admiration for the men saying ‘ Believe me , I shall never more take off my hat for anything less than a British seaman ’ .