This French force was able to capture a number of East Indiamen and disrupt trade routes across the Indian Ocean by raiding the convoys in which the merchant ships travelled.

Forced to confront this enemy, Admiral Albemarle Bertie at the Cape of Good Hope ordered Commodore Josias Rowley to blockade the French islands and prevent their use as raiding bases.

The British were able to slowly reduce the French presence by eliminating their bases through limited invasions, but suffered a major setback at Grand Port in August 1810 and were forced onto the defensive in the autumn.

Hamelin was eventually defeated only after being personally captured on his flagship Vénus by Rowley, shortly before substantial reinforcements arrived under Bertie to seize Isle de France.

Throughout the campaign Hamelin was unable to secure reinforcement from France—almost all attempts to break through the British blockade of French ports proved futile and only one frigate successfully reached the Indian Ocean before the surrender of Isle de France.

[1] 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.

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.

[5] 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.

[7] 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.

[9] 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[who?]

[10] 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.

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.

[12] 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.

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.

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.

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.

Advancing rapidly against weak French defences, the British landing parties forced the island's governor Chrysostôme de Sainte-Suzanne to surrender the following day.

With the harbour secure, Willoughby raided along the coastline while Pym, reinforced by Henry Lambert in Iphigenia and Lucius Curtis in Magicienne, blockaded Port Napoleon.

Only Nereide reached Duperré's line and Willoughby's initial attack was so determined that the entire French squadron was rapidly driven ashore, only Bellone remaining in a position to exchange fire with the British frigate.

[30] A fortunate shot from Bellone cut Nereide's anchor cable and the British frigate swung around, presenting her stern to the French ships which raked her repeatedly.

[32] On the morning of 28 August, Iphigenia, laden with survivors from the grounded frigates, was confronted by Hamelin and his main squadron, which had taken seven days to travel from Port Napoleon.

[36] In September, October and November 1810, British navy and army forces arrived from Madras, Bombay and the Cape of Good Hope, warships joining Rowley's squadron off Isle de France and soldiers gathering at Rodrigues.

The buildup of forces was prompted by the defeat at Grand Port combined with the heavy losses of East Indiamen during 1809 and 1810; the British authorities were determined to end the threat posed by the French squadron on Isle de France before the hurricane season made travel in the region too dangerous.

In addition, food supplies were running low due to the large number of British prisoners on the island and morale had collapsed in the aftermath of Hamelin's defeat.

With strategic bases placed along their trade routes, British convoys were assured a greater degree of safety and the Royal Navy provided with the infrastructure to operate worldwide.