The Mauritius campaign of 1809–1811 was a minor military campaign of the Napoleonic Wars fought between British and French forces over France's Indian Ocean colonies of Isle de France and Isle Bonaparte. Lasting from the spring of 1809 to the spring of 1811, the campaign saw the British and French navies deploy substantial frigate squadrons to either protect or disrupt British-flagged shipping in the region. In a war in which the Royal Navy was almost universally dominant at sea, the campaign is especially notable for the local superiority enjoyed by the French Navy in autumn 1810 following their victory at the Battle of Grand Port, the British navy's most significant defeat in the campaign.
British commanders had been planning an operation against Isle de France since occupying the Dutch Cape Colony in 1806 and destroying the Dutch squadron in Java in 1807, but acted earlier than planned following the arrival from France of a powerful frigate squadron under Commodore Jacques Félix Emmanuel Hamelin in late 1808. Hamelin's squadron captured several British East Indiamen and disrupted Britain's trade routes across the Indian Ocean by raiding the convoys in which its merchantmen travelled. Forced to confront this threat, Admiral Albemarle Bertie at the Cape Colony ordered Commodore Josias Rowley to blockade the French colonies and prevent their use use as raiding bases.
For the next two years, the British raided the French colonies' ports and anchorages, while the French continued to target British merchantmen. The British occupied Rodrigues in 1809 and Isle Bonaparte in 1810, but their defeat at Grand Port forced them onto the defensive. Hamelin, unable to secure reinforcements from France, was captured on his flagship Vénus by Rowley in late 1810 shortly before reinforcements under Bertie arrived and occupied Isle de France, renaming it Mauritius. A French squadron which had arrived too late was defeated by the British off Madagascar in May 1811, leaving Britain in complete control of the Indian Ocean. The British kept Mauritius but returned Isle Bonaparte to France in 1814.
Background
The Indian Ocean was a vital part of the chain of trade links that connected the British Empire. Merchant ships from China, Arabia and East Africa crossed it regularly and at its centre was the British-held continent of India, from which heavily laden East Indiamen brought millions of pounds worth of trade goods to Britain every year. Trade with India was vital to the financial security of Britain and consequently the trade routes across the Indian Ocean were a high priority for protection from the Royal Navy and at serious risk from French raiders. The outbreak of the Napoleonic Wars in 1803, following the brief Peace of Amiens that had ended the French Revolutionary Wars, placed the Indian Ocean trade routes under threat from Dutch cruisers operating from Cape Town and the Dutch East Indies and French ships operating from the colonies of Isle de France and Isle Bonaparte. In 1806, British forces occupied the Dutch Cape Colony and by December 1807 had destroyed the Dutch navy's East Indies squadron; these actions led to the elimination of the Dutch as a threat to British overseas interests. However, France's Indian Ocean colonies were far more defensible: heavily fortified, garrisoned by regular French soldiers and several months voyage from the nearest British port, they presented a much greater challenge to the limited British forces available in the region.
At the beginning of the war, as in the preceding conflict, French privateers operated from the islands, including a fleet of small vessels run by Robert Surcouf. Supplementing these ships were vessels of the French Imperial Navy, principally the frigate Piémontaise (captured in March 1808) and the old frigates Sémillante and Canonnière. These ships operated independently of one another and achieved minor successes against smaller British warships and merchant vessels but were not powerful enough to have a serious effect on the Indian Ocean trade routes. In August 1808, Sémillante and Canonnière were downgraded to armed storeships and sent back to France. To replace these ships, four large frigates under Jacques Hamelin were sent to Governor Charles Decaen on Isle de France in the late autumn of 1808. These vessels, Vénus, Manche, Caroline and Bellone were large and powerful ships under orders to operate from Isle de France and Isle Bonaparte against British trade in the Indian Ocean. Based on Isle de France, these frigates had access to large numbers of unemployed sailors and several fortified anchorages from which to launch raids on the British trade routes. A fifth frigate, Niémen, was to have joined the force in the summer of 1809, but was intercepted and captured within hours of leaving France at the action of 6 April 1809.
To counteract the French deployment to the region, a small British force was organised by Vice-Admiral Albemarle Bertie at Cape Town under the command of Commodore Josias Rowley, with orders to blockade Isle de France and Isle Bonaparte and seize or destroy any French ships that operated from the islands. To perform this task, Rowley was given the old ship of the line HMS Raisonnable, the fourth rate HMS Leopard, frigates HMS Nereide, HMS Sirius and HMS Boadicea and a number of smaller ships. Both the British and the French squadrons reached the Indian Ocean in the spring of 1809.
Campaign
First exchanges
Hamelin's forces were immediately effective: Caroline attacked a westbound convoy of East Indiamen in the action of 31 May 1809 in the Bay of Bengal and captured two, the Streatham and Europe. She seized several other small vessels on the cruise before slipping back to Isle Bonaparte with her prizes in August. Hamelin too cruised in the Bay of Bengal during the summer and autumn, Vénus accompanied by Manche and the corvette Créole. On 26 July, Vénus captured the Honourable East India Company (HEIC) warship Orient off the Nicobar Islands.
Rowley's force had also been active: Nereide under Captain Robert Corbet captured a number of small vessels off Port Napoleon in the late spring, including the brig Aigle, which he sent to the Cape of Good Hope with a prize crew that mutinied, killed their officer and took the ship to Isle Bonaparte. The brig HMS Otter, under Captain Nesbit Willoughby, raided an anchorage at Rivière Noire District on 14 August, capturing a coastal vessel (which he later had to abandon) under heavy fire. Willoughby also recaptured Aigle shortly afterwards. Rowley himself had chased the Bellone in Raisonnable as the French ship emerged from Port Napoleon on 17 August, but had been unable to catch her. Most significant of all was the seizure of the island of Rodrigues by a British Army force from India under Lieutenant Colonel Henry Keating. This small island was close enough to Isle de France to provide an effective base for the British blockade squadron and a staging area for a future invasion of the French islands.
Rowley's first co-ordinated action was prompted by the return of Caroline with her prizes. Sheltering under the guns of Saint-Paul harbour, Caroline made an inviting target for an expeditionary force from Rodrigues in practice for the anticipated invasion of the whole island. On 21 September, a force of over 600 soldiers, sailors and Royal Marines under Keating and Willoughby landed on Isle Bonaparte and marched around the town's seaward fortifications, storming them from the rear at first light. Capturing each in succession and routing opposition from French militia, the force secured the gun batteries overlooking the port, allowing Rowley to bring his squadron directly into the harbour and bombard the shipping anchored within. The French naval officers, outnumbered and unsupported, drove their ships on shore and abandoned them, allowing the British to seize and carry off Caroline, the two captured East Indiamen and a number of smaller vessels. French attempts to recapture the town were undermined by the failure of the island's commander, General Nicolas Des Bruslys, to engage the British with his main force. Des Bruslys later committed suicide. With the garrison leaderless, a truce was agreed that granted the British five days in control of the town. In this time they were able to remove all government supplies and demolish the town's government buildings. Rowley and his force eventually departed from Saint-Paul on 28 September. As a reward for their services, Willoughby was promoted to command Nereide and Corbet sent back to Britain in Caroline, renamed HMS Bourbonaise.
While Rowley was attacking Saint-Paul, Hamelin and his ships Vénus, Manche, Bellone and Créole were cruising in the Bay of Bengal. On 10 October, Hamelin attacked the Honourable East India Company's base at Tappanooly on Sumatra and burnt it to the ground: the entire population was taken prisoner, although the women were sent to Padang in a small schooner. On 2 November, the British brig HMS Victor was captured by Bellone after a running fight and two weeks later Hamelin intercepted a convoy of three East Indiamen, Windham, Streatham and Charlton, capturing all three in the action of 18 November 1809. On 22 November, Bellone chased, caught and defeated the 52-gun Portuguese frigate Minerva. With their crews now dispersed among their prizes and cyclone season rapidly approaching, Hamelin ordered his squadron back to Isle de France. En route, the convoy was struck by a storm and scattered: Vénus was especially badly damaged and at one point was only saved from sinking by the efforts of the English prisoners aboard. By 31 December, all ships had returned to Isle de France except Windham, which had been recaptured by the recently arrived British frigate HMS Magicienne.
Invasion of Isle Bonaparte
The French Navy considered 1809 to have been a success; they reinforced Hamelin with one frigate, the only one able to slip through the British blockade of French ports, the Astrée, which arrived early in 1810. Hamelin was quick to act at the end of the cyclone season: Captain Guy-Victor Duperré in Bellone and Captain Pierre Bouvet in the ex-Portuguese Minerva (renamed Minerve) departed Isle de France on 14 March to raid in the Bay of Bengal and subsequently along the South-East coast of Africa. Despite an initial lack of targets, Duperré's cruise was successful: in July he discovered and defeated a convoy of East Indiamen at the action of 3 July 1810, seizing Windham for a second time and Ceylon.
Shortly after Duperré's departure, a British squadron under Captain Henry Lambert consisting of HMS Magicienne, HMS Iphigenia and HMS Leopard arrived off Isle de France to restore the blockade. Rowley subsequently increased Lambert's forces, detaching Willoughby in Nereide with instructions to raid coastal anchorages on the island. On 24 April, Willoughby sighted the recently arrived Astrée, and on 30 April attacked the protected anchorage at Jacolet. His target was a large French merchant ship protected by two batteries and a detachment of regular infantry. Landing at night under heavy fire, Willoughby's men seized one battery, drove off a French attack on their beachhead and captured the second battery despite having to advance across a river, under fire, in broad daylight. On returning to their boats, Willoughby's men were attacked by a second French force which they also routed and drove more than a mile inland. Shortly afterwards however, Willoughby was seriously wounded when a musket he was firing exploded, shattering his jaw. As a result, he was forced to spend several months recovering from his injuries on Rodriguez.
During the late spring, Rowley's force was shorn of Raisonnable and Leopard, sent back to Britain for refit. Although reduced to five frigates and a few smaller vessels, Rowley began preparations for the invasion of Isle Bonaparte by increasing the number of soldiers available on Rodriguez with detachments sent from Madras. Isle Bonaparte was the smaller of the French bases and was more weakly defended, the island's defences damaged in the raid at Saint Paul the previous year. On 24 June, Rowley withdrew Boadicea and Nereide to Rodriguez and collected Keating's force of over 3,000 soldiers. Meeting the rest of his squadron off Isle Bonaparte, Rowley organised two landings on 7 July, either side of the island's capital Saint Denis. Advancing rapidly against weak French defences, the British landing parties forced the island's governor Chrysostôme de Sainte-Suzanne to surrender the following day. It was in the days after this operation that Commander Matthew Flinders, an explorer who had been arrested by Decaen at Port Napoleon eight years earlier and held prisoner despite instructions from Napoleon himself to release him, was freed. Flinders was able to supply Rowley and later Bertie with detailed information about the defences on Isle de France.
Battle of Grand Port
Even before the French garrison on Isle Bonaparte had surrendered, Rowley had turned his attention eastwards to Isle de France. The British commander had decided that the best way to eliminate the threat of Hamelin's squadron was to blockade the island's principal ports by seizing the coral islands that marked the entrances to the harbours through the complicated coral reefs that surrounded Isle de France. These islands were fortified, and once in British hands could prevent French ships leaving or entering the harbours, effectively containing Hamelin's ships until Rowley was ready to launch an invasion. Detailed to lead this campaign was Captain Samuel Pym in Sirius and Willoughby in Nereide, with instructions to begin by seizing Île de la Passe at the entrance to the harbour of Grand Port on the south-eastern coast of Isle de France.