French warship. She was still under construction on the resumption of the war in 1803 after the Peace of Amiens, but was launched later that year. She was fitted out with masts, yards and rigging, and in late 1804 she was commissioned under Commodore Esprit-Tranquille Maistral. Trafalgar campaign Neptune joined the rest of the Toulon fleet preparing to sail for the West Indies on 21 October 1804 under the command of Vice-Admiral Pierre-Charles Villeneuve. The fleet was to transport 6,500 troops to attack British possessions in the Caribbean, but was unable to leave Toulon owing to the presence of a British fleet under Vice-Admiral Horatio Nelson, that was blockading the port. It was not until early January that Villeneuve judged the situation favourable enough to make a sortie. Neptune sailed with the 20-strong fleet on 17 January, but were sighted by the patrolling frigates of Nelson's inshore squadron. Villeneuve struggled on, but bad weather in the Gulf of Lyons dispersed his fleet, and fearing an attack on his disorganised forces, returned to Toulon three days after setting out. Villeneuve had in fact managed to give Nelson the slip. The two patrolling frigates, and , had rushed to report the news to Nelson, anchored at La Maddalena, and in so doing, left the French unobserved. Nelson had rushed his fleet to sea, anticipating that Villeneuve would heading east. Nelson spent nearly six weeks sailing back and forth across the Mediterranean through heavy seas while the French remained in port, before news finally reached him of Villeneuve's location. It was not until March that the French made another attempt to break out of Toulon, putting to sea on 29 March. Neptune formed part of Villeneuve's division, consisting of the flagship, the 80-gun Bucentaure, and the 74-gun ships , , and . The other division was commanded by Rear-Admiral Pierre Dumanoir le Pelley, flying his flag aboard the 80-gun Formidable, and accompanied by the 80-gun Indomptable, and the 74-gun ships , and . Accompanying the fleet were six frigates and two brigs. The French fleet reached Cartagena on 6 April, having evaded Nelson through sheer chance, and pressed on from there, sailing through the Strait of Gibraltar on 8 April. After resupplying briefly at Cadiz, the fleet sailed to the West Indies, arriving at Fort de France, Martinique on 14 May, where they were joined over the next two days by six Spanish