The Anglo-Spanish War of 1654–1660 was fought between the Commonwealth of England and Habsburg Spain. It was driven by the economic and religious rivalry between the two countries, with each side attacking the other's commercial and colonial interests in various ways, such as privateering and naval expeditions.
In 1655, an English amphibious expedition invaded Spanish territory in the Caribbean, eventually capturing the island of Jamaica. In 1657, England formed an alliance with France, merging the Anglo-Spanish war with the larger Franco-Spanish War, with major land actions that took place in the Spanish Netherlands.
Although the war was terminated after the Restoration of King Charles II of England in 1660, tensions in the Caribbean with regard to the English possession of Jamaica kept the conflict going intermittently for over ten years. This included raids on Spanish territory by notable Privateer Henry Morgan. The war officially ended with two peace treaties, which were signed at Madrid in 1667 and 1670.
When the First Anglo-Dutch War came to an end, Cromwell turned his attention to the conflict between France and Spain, both traditional rivals of England. France and Spain were both of the Roman Catholic faith, anathema to Cromwell, who believed it is God's will that Protestantism should prevail in Europe. However, he considered Spain to be the greater threat to the Protestant cause, and thus pragmatically allied his nation with France. By going to war with Spain, he also sought a return to a policy of commercial opportunism pursued in the days of Elizabeth I and subsequently abandoned by her Stuart successors. Cromwell's attack on Spanish trade and treasure routes immediately recalled the exploits of Francis Drake and Walter Raleigh; and it is not by accident that printed accounts of their activities began to circulate in England at this time. There was, however, one important difference: alongside silver and gold a new treasure was becoming ever more important – sugar. This meant occupation of territory, a step beyond the piracy pursued in Elizabethan days.
During the first year of the Protectorate, Cromwell conducted negotiations with the French statesman Cardinal Mazarin, resulting in the drafting of an Anglo-French alliance against Spain in October 1655. The alliance had an added benefit: France, which was currently offering refuge to the Stuarts, would now be disinclined to assist them in reclaiming the English throne.
Meanwhile, Cromwell had already launched the Western Design against Spain's colonies in the Spanish West Indies. The fleet left Portsmouth in late December 1654 and arrived in the West Indies in January. In May 1655, an English amphibious expedition led by General at Sea William Penn, father of the founder of Pennsylvania, and General Robert Venables invaded Spanish territory in the West Indies with the objective of capturing Hispaniola. It was one of the strongest ever to sail from England, with some 3,000 marines under the command of General Robert Venables, further reinforced in Barbados, Montserrat, and St. Kitts and Nevis.
Although Cromwell had previously been interested in the possible acquisition of Hispaniola island, the expedition's commanders were given the freedom to determine their own priorities in the circumstances they faced on arrival. Several options were considered, including a landing on the coast of Guatemala or on Cuba. Both were discounted, as Penn and Venables decided to attempt to repeat Drake's attack on Santo Domingo on Hispaniola. However, the 1655 Siege of Santo Domingo failed because the Spanish had improved their defences in the face of Dutch attacks earlier in the century. Cromwell, on the other hand, saw the Hispaniola defeat as God's judgement. Despite various subsequent successes, the defeat made the whole operation against the Spanish West Indies a general failure. Venables and Penn were imprisoned therefore in the Tower of London on their arrival on England.
Jamaica was the casus belli that resulted in the actual Anglo-Spanish War in 1655. Weakened by fever, the English force then sailed west for the Colony of Santiago (present-day Jamaica), the only Spanish West Indies island that did not have new defensive works. They landed in May 1655 at a place called Santiago de la Vega, now Spanish Town. They came, and they stayed, in the face of prolonged local resistance that was reinforced by troops sent from Spain and New Spain (México). In 1657 the English Governor invited the Buccaneers to base themselves at Port Royal on Santiago, to deter the Spanish from recapturing the island. For England, Jamaica was to be the "dagger pointed at the heart of the Spanish Empire", although in fact it was a possession of little value then. Cromwell, despite all difficulties, was determined that the presence should remain, sending reinforcements and supplies. New Spanish troops, sailing from Cuba, lost the Battle of Ocho Rios in 1657 and the Battle of Rio Nuevo in 1658, failing in their attempts to retake Jamaica. Nevertheless, the fear of another invasion meant that the English Governor of Jamaica Edward D'Oyley felt his new duty was to organize the defence of the island against the Spanish. By using the tactic of attacking instead of defending, he sent out Christopher Myngs to raid Spanish colonial cities and bases. Tolú and Santa Marta were among them in 1658 and the following year Cumana, Puerto Caballos and Coro were plundered and devastated and Myngs returned to Jamaica with a vast amount of plunder and treasure.
In April 1656 English Admiral Robert Blake with a fleet of around forty warships, fireships and supply vessels sailed to blockade the Spanish port of Cádiz which continued throughout the summer. The Spanish remained on the defensive and took no aggressive action against the English fleet. In mid-June, Captain Edward Blagg sailed with eight ships to raid ports in northern Spain. On 24 June, Blagg raided Vigo, where a number of ships in the harbour were destroyed. While Blake replenished his water supplies on the African coast, a detachment of five frigates under a Captain Smith raided Malaga in southern Spain on 19 July. Smith sank nine Spanish ships, spiked the harbour guns and bombarded the town. A similar raid on Alicante was unsuccessful, but the threat of attack disrupted trade all along the coasts of Spain. On the evening of 8 September, one of Blake's captains, Richard Stayner, intercepted a Spanish treasure fleet and captured or sank all but two of its ships. The loss of the cargoes of the ships captured or sunk by the English was a serious blow to the economy of Spain with an estimated loss of £2,000,000. For the first time in naval history, Blake kept the fleet at sea throughout an entire winter in order to maintain the blockade against Spain.
In February 1657, Blake received intelligence that the plate fleet from New Spain was on its way across the Atlantic. Leaving two ships to watch Cádiz, Blake sailed from there to attack the plate fleet, which had docked at Santa Cruz on Tenerife in the Canary Islands to await an escort to Spain. In April in the Battle of Santa Cruz de Tenerife, Blake completely destroyed the Spanish merchant convoy—the West Indian Fleet—however, the fleet had landed the bullion before the battle. Blake was unable to seize it, but it was also unavailable to the government in Madrid.
The short-term effect of Blake's blockade of Spain and his victory at Santa Cruz was the disruption of the Spanish economy, which depended upon silver and gold from the Americas and thereby damaged Spain's capacity for waging war. The English lost 1,500 to 2,000 merchant ships to Spanish privateers and instead of using captured English ships to replace their destroyed convoys, the Spanish government placed the care of Spanish trade in the hands of neutral Dutch merchantmen.
An Anglo-French alliance against Spain was established when the Treaty of Paris was signed in March 1657. Based on the terms of the treaty, the English would join with France in her continuing war against Spain in Flanders. France would contribute an army of 20,000 men, England would contribute both 6,000 troops and the English fleet in a campaign against the Flemish coastal fortresses of Gravelines, Dunkirk and Mardyck. It was agreed that Gravelines would be ceded to France, Dunkirk and Mardyck to England. Dunkirk, in particular, was on the Commonwealth's mind mainly because of the privateers that were causing damage to the mercantile fleet. For Cromwell and the Commonwealth, the question of possession of Dunkirk thus passed from regional diplomatic possibility to urgent political necessity.