At his head-quarters at St. Lucia in April, 1780, Rodney heard that the French fleet under De Guichen had sailed from Martinique. On the 17th he fought an indecisive action with the enemy, an action notable for what Rodney attempted, not for what he accomplished. Twice again on later days Rodney met De Guichen, but none of the three battles did more than inflict mutual loss on the combatants, without producing any decisive result. The campaign was, like so many others in the West Indies, a struggle for the temporary possession of this or that port or island, De Guichen's whole strategy being based on the idea of avoiding the risks of a close engagement that might imperil his fleet, and trying to snatch local advantages when he could elude his enemy.

In 1781 Rodney was compelled by ill-health temporarily to give up the West Indian command and return to England. In the spring of 1782 he was again sent to the West Indies, at a moment when the situation of affairs was most menacing for British power beyond the Atlantic. Cornwallis had been forced to surrender at Yorktown, and the success of the revolted American colonies was now assured. The French fleet in the West Indies had been joined by reinforcements under the Comte de Grasse, who had gone out as commander-in-chief, taking with him a considerable military force that was to combine with an expedition from the Spanish American colonies, not for the capture of some small islands in the Antilles, but for the conquest of Jamaica, the centre of British power and British trade in the West Indian seas.

Kempenfeldt, a good sailor (now remembered chiefly as the admiral who "went down with twice three hundred men," when the "Royal George" sank at Spithead), dispersed and destroyed at the mouth of the Channel a large French convoy of supplies for De Grasse, and drove the squadron that protected it into Brest. With his task thus lightened, Rodney put to sea with four ships of the line, and after a stormy passage reached Barbadoes on 19 February, 1782. Sailing thence to Antigua, he formed a junction with and took command of the West Indian fleet, which Hood had commanded during his absence in England. From Antigua he took the fleet to St. Lucia, where he established his head-quarters in Gros Islet Bay. St. Lucia was the favourite base of operations of our West Indian fleets in the old wars, and the scene of much desperate fighting by land and sea. The year before De Grasse had failed in an attempt to seize it.

The fleet of the Comte de Grasse was only some forty miles away to the northward. It lay at Martinique, in the bay of Fort Royal (now Fort de France). Though it has nothing to do with the fortunes of Rodney and De Grasse, it is interesting to note that in a convent school looking out on the bay there was just then a little schoolgirl named Josephine de la Pagerie, daughter of an artillery lieutenant in the garrison, who was to live to be Empress of the French, when France was the mistress of Europe.

During the month of March both fleets were busy preparing for sea. Rodney was reinforced from England, and a small squadron from Brest joined De Grasse. The reinforcements received during March had given Rodney the advantage of numbers. He had thirty-six sail of the line to oppose the thirty that were with De Grasse at Martinique. In the English fleet there were five great three-deckers, three of them carrying 98 and two of them 90 guns. There were twenty-one 74's, a 70-gun ship, and nine 64's. In the French fleet there was one of the largest war vessels then afloat, De Grasse's flagship, the "Ville de Paris," of 104 guns. There were five ships of 80 guns, twenty of 74, one of 70, and three of 64. This enumeration gives Rodney an advantage of six ships and more than two hundred guns. It is quite true that the ships of the same rating in the French service were generally larger than the English, but even apart from numbers, the latter had advantages in armament that were more important than any trifling difference in size. The English guns were mostly mounted on an improved system that gave a larger arc of training fore and aft, the practical result being that as ships passed each other the Frenchman was kept longer under fire than the Englishman. Further, the English ships mounted, besides the guns counted in their armament, a number of carronades, mounted on the upper decks, short guns of large calibre, throwing a heavy shot when the fighting was carried on at close quarters, a weapon not yet introduced in the French navy. Thanks to these improvements in the armament of his ships, Rodney had an advantage in gun-power beyond the mere superiority in numbers of ships and guns. He had a further advantage in the fact that a larger number of his ships were copper-sheathed. This meant less fouling while the ships were waiting at their anchorage, and therefore better speed for the English when they put to sea.

De Grasse was encumbered with a large convoy of merchantmen and storeships, and many of his ships were overcrowded with the troops destined for the descent on Jamaica. It was expected that when he sailed it would be to form, in the first instance, a junction with the Spanish part of the expedition off San Domingo. Rodney kept his fleet at St. Lucia, ready to weigh anchor on the shortest notice, and a smart frigate, the "Andromache" (commanded by Captain Byron, grandfather of the poet), cruised off Martinique, watching the Frenchman.

At dawn on 8 April Byron saw that the French were coming out, and he hastened to St. Lucia under press of sail with the news. Off the port he flew the signal that told Rodney that De Grasse was at sea. Anchors came up and sails were shaken out, and Rodney set off in pursuit, knowing that De Grasse had a very few hours' start of him.

The few hours did not count for much, provided the English admiral could once get on the Frenchman's track. The danger of missing him could only arise from making at the outset a wrong judgment as to the course on which the enemy would sail. It was De Grasse's business to avoid a battle until he had safely taken his huge convoy to San Domingo and joined hands with his Spanish allies. Rodney judged that he would most likely follow the long curve of the chain of islands that fringe the Caribbean Sea, steering by Puerto Rico for San Domingo. In the night of the 8th the English fleet passed Martinique. Next morning it was off the west coast of Dominica, making good speed, and away to the northward a far-spreading crowd of sails showed that Rodney had guessed rightly. The French fleet and convoy were in sight.

Dominica is a mass of volcanic ridges, falling to the seaward in precipitous cliffs, rising landward tier above tier and shooting up into rocky spires that culminate in the towering peak of the Morne Diablotin, five thousand feet high. Under the shelter of this rugged island, while the prevailing trade wind blows steadily from the eastward, there are sudden calms, or irregular flaws of wind blowing now from one point, now from another, diverted by the irregular ridges of the high land. This April morning the sun had hardly risen when the wind fell, and the two fleets drifted slowly, with loose-hanging sails. Near the north end of the island lay the convoy. A little to the southward De Grasse's thirty battleships straggled in a long line over some six miles of sunlit sea. Off the centre and south of the island Rodney's larger fleet was stretched out in line ahead. It was formed in three divisions. Hood, in the 90-gun "Barfleur," commanded the van. Rodney, with his flag flying in a tall three-decker, the "Formidable," of 98 guns, was in the centre. The rear was commanded by Rear-Admiral Samuel Drake, a namesake and descendant of that other Drake whose name had been the terror of the West Indian seas in Elizabethan days.

Suddenly there came a flaw of wind sweeping from the south round the end of the island, so narrow that most of the English fleet hardly felt it. It filled the sails of Hood's ships in the van, and they steered for two French battleships that dropped astern of their consorts. One of the Frenchmen passed close under the tiers of guns in the leading English ship, but not a shot was fired at her as she swept by and rejoined her consorts. Rodney had not yet flown the signal for battle, and these were still the days when personal enterprise and decision were not encouraged among the captains of a fleet.