The naval operations of this war were languid and confused. They are complicated by the fact that they were entangled with the Spanish war, which broke out in 1739 in consequence of the long disputes between England and Spain over their conflicting claims in America. Until the closing years they were conducted with small intelligence or spirit. The Spanish government was nerveless, and sacrificed its true interest to the family ambition of the king Philip V., who wished to establish his younger sons as ruling princes in Italy. French administration was corrupt, and the government was chiefly concerned in its political interests in Germany. The British navy was at its lowest point of energy and efficiency after the long administration of Sir Robert Walpole. Therefore, although the war contained passages of vigour, it was neither interesting nor decisive on the sea.
War on Spain was declared by Great Britain on the 23rd of October 1739. It was universally believed that the Spanish colonies would fall at once before attack. A plan was laid for combined operations against them from east and west. One force, military and naval, was to assault them from the West Indies under Admiral Edward Vernon. Another, to be commanded by Commodore George Anson, afterwards Lord Anson, was to round Cape Horn and to fall upon the Pacific coast. Delays, bad preparations, dockyard corruption, and the unpatriotic squabbles of the naval and military officers concerned caused the failure of a hopeful scheme. On the 21st of November 1739 Admiral Vernon did indeed succeed in capturing the ill-defended Spanish harbour of Porto Bello (in the present republic of Panama) - a trifling success to boast of. But he did nothing to prevent the Spanish convoys from reaching Europe. The Spanish privateers cruised with destructive effect against British trade, both in the West Indies and in European waters.
When Vernon had been joined by Sir Chaloner Ogle with naval reinforcements and a strong body of troops, an attack was made on Cartagena in what is now Colombia (March 9-April 24, 1741). The delay had given the Spanish admiral, Don Bias de Leso, time to prepare, and the siege failed with a dreadful loss of life to the assailants. Want of success was largely due to the incompetence of the military officers and the brutal insolence of the admiral. The war in the West Indies, after two other unsuccessful attacks had been made on Spanish territory, died down and did not revive till 1748. The expedition under Anson sailed late, was very ill provided, and less strong than had been intended. It consisted of six ships and left England on the 18th of September 1740. Anson returned alone with his flagship the "Centurion" on the 15th of June 1744. The other vessels had either failed to round the Horn or had been lost. But Anson had harried the coast of Chile and Peru and had captured a Spanish galleon of immense value near the Philippines. His cruise was a great feat of resolution and endurance.
While Anson was pursuing his voyage round the world, Spain was mainly intent on the Italian policy of the king. A squadron was fitted out at Cadiz to convey troops to Italy. It was watched by the British admiral Nicholas Haddock. When the blockading squadron was forced off by want of provisions, the Spanish admiral Don José Navarro put to sea. He was followed, but when the British force came in sight of him Navarro had been joined by a French squadron under M. de Court (December 1741). The French admiral announced that he would support the Spaniards if they were attacked and Haddock retired. France and Great Britain were not yet openly at war, but both were engaged in the struggle in Germany - Great Britain as the ally of the queen of Hungary, Maria Theresa; France as the supporter of the Bavarian claimant of the empire. Navarro and M. de Court went on to Toulon, where they remained till February 1744. A British fleet watched them, under the command of admiral Richard Lestock, till Sir Thomas Mathews was sent out as commander-in-chief, and as minister to the court of Turin. Partial manifestations of hostility between the French and British took place in different seas, but avowed war did not begin till the French government issued its declaration of the 30th of March, to which Great Britain replied on the 31st. This formality had been preceded by French preparations for the invasion of England, and by a collision between the allies and Mathews in the Mediterranean (see Toulon, Battle of). On the 11th of February a most confused battle was fought, in which the van and centre of the British fleet was engaged with the rear and centre of the allies.
Lestock, who was on the worst possible terms with his superior, took no part in the action. He endeavoured to excuse himself by alleging that the orders of Mathews were contradictory. Mathews, a puzzle-headed and hot-tempered man, fought with spirit but in a disorderly way, breaking the formation of his fleet, and showing no power of direction. The mismanagement of the British fleet in the battle, by arousing deep anger among the people, led to a drastic reform of the British navy which bore its first fruits before the war ended.
The French invasion scheme was arranged in combination with the Jacobite leaders, and soldiers were to be transported from Dunkirk. But though the British government showed itself wholly wanting in foresight, the plan broke down. In February 1744, a French fleet of twenty sail of the line entered the Channel under Jacques Aymar, comte de Roquefeuil, before the British force under admiral John Norris was ready to oppose him. But the French force was ill equipped, the admiral was nervous, his mind dwelt on all the misfortunes which might possibly happen, and the weather was bad. M. de Roquefeuil came up almost as far as the Downs, where he learnt that Sir John Norris was at hand with twenty-five sail of the line, and thereupon precipitately retreated. The military expedition prepared at Dunkirk to cross under cover of Roquefeuil's fleet naturally did not start. The utter weakness of the French at sea, due to long neglect of the fleet and the bankrupt state of the treasury, was shown during the Jacobite rising of 1745, when France made no attempt to profit by the distress of the British government.
The Dutch having by this time joined Great Britain, made a serious addition to the naval power opposed to France, though Holland was compelled by the necessity for maintaining an army in Flanders to play a very subordinate part at sea. Not being stimulated by formidable attack, and having immediate interests both at home and in Germany, the British government was slow to make use of its latest naval strength. Spain, which could do nothing of an offensive character, was almost neglected. During 1745 the New England expedition which took Louisburg (April 30-June 16) was covered by a British naval force, but the operations were in a general way sporadic, subordinated to the supply of convoy, or to unimportant particular ends. In the East Indies, Mahé de la Bourdonnais made a vigorous use of a small squadron to which no effectual resistance was offered by the British naval forces. He captured Madras (July 24-September 9, 1746), a set-off for Louisburg, for which it was exchanged at the close of the war.
In the same year a British combined naval and military expedition to the coast of France - the first of a long series of similar ventures which in the end were derided as "breaking windows with guineas" - was carried out during August and October. The aim was the capture of the French East India company's dockyard at L'Orient, but it was not attained.
From 1747 till the close of the war in October 1748 the naval policy of the British government, without reaching a high level, was yet more energetic and coherent. A closer watch was kept on the French coast, and effectual means were taken to intercept communication between France and her American possessions. In the spring information was obtained that an important convoy for the East and West Indies was to sail from L'Orient. In the previous year the British government had allowed a French expedition under M. d'Anville to fail mainly by its own weakness. In 1747 a more creditable line was taken. An overwhelming force was employed under the command of Anson to intercept the convoy in the Channel. It was met, crushed and captured, or driven back, on the 3rd of May. On the 14th of October another French convoy, protected by a strong squadron, was intercepted by a well-appointed and well-directed squadron of superior numbers - the squadrons were respectively eight French and fourteen British - in the Bay of Biscay. The French admiral Desherbiers de l'étenduère made a very gallant resistance, and the fine quality of his ships enabled him to counteract to some extent the superior numbers of Sir Edward Hawke, the British admiral.
While the war-ships were engaged, the merchant vessels, with the small protection which Desherbiers could spare them, continued on their way to the West Indies. Most of them were, however, intercepted and captured in those waters. This disaster convinced the French government of its helplessness at sea, and it made no further effort.
The last naval operations took place in the West Indies, where the Spaniards, who had for a time been treated as a negligible quantity, were attacked on the coast of Cuba by a British squadron under Sir Charles Knowles. They had a naval force under Admiral Regio at Havana. Each side was at once anxious to cover its own trade, and to intercept that of the other. Capture was rendered particularly desirable to the British by the fact that the Spanish homeward-bound convoy would be laden with the bullion sent from the American mines. In the course of the movement of each to protect its trade, the two squadrons met on the 1st of October 1748 in the Bahama Channel. The action was indecisive when compared with the successes of British fleets in later days, but the advantage lay with Sir Charles Knowles. He was prevented from following it up by the speedy receipt of the news that peace had been made in Europe by the powers, who were all in various degrees exhausted. That it was arranged on the terms of a mutual restoration of conquests shows that none of the combatants could claim to have established a final superiority.
The conquests of the French in the Bay of Bengal, and their military successes in Flanders, enabled them to treat on equal terms, and nothing had been taken from Spain.
The war was remarkable for the prominence of privateering on both sides. It was carried on by the Spaniards in the West Indies with great success, and actively at home. The French were no less active in all seas. Mahé de la Bourdonnais's attack on Madras partook largely of the nature of a privateering venture. The British retaliated with vigour. The total number of captures by French and Spanish corsairs was in all probability larger than the list of British - partly for the reason given by Voltaire, namely, that more British merchants were taken because there were many more British merchant ships to take, but partly also because the British government had not yet begun to enforce the use of convoy so strictly as it did in later times.
See Beatson's Naval and Military Memoirs (London, 1804); La Marine militaire de la France sous le règne de Louis XV, by G. Lacour-Gayet (Paris, 1902); The Royal Navy, by Sir W. L. Clowes and others (London, 1891, etc.).