After Spain abandoned its former policy of neutrality by signing the family compact with France, resulting in a British declaration of war on Spain in January 1762, the British government decided to mount an attack on the important Spanish fortress and naval base of Havana, with the intention of weakening the Spanish presence in the Caribbean and improving the security of its own North American colonies.

A strong British naval force consisting of squadrons from Britain and the West Indies, and the military force of British and American troops it convoyed, were able to approach Havana from a direction that neither the Spanish governor nor the Admiral expected and were able to trap the Spanish fleet in the Havana harbour and land its troops with relatively little resistance.

The fortress eventually fell after the officer in charge of Morro Castle, Luis Vicente de Velasco, was mortally wounded by a stray bullet.

The capture of Morro Castle led to the eventual fall of the rest of the fortifications and the surrender of the city, the remaining garrison, and the naval forces present, before the hurricane season began.

The surrender of Havana led to substantial rewards for the British naval and military leaders and smaller amounts of prize money for other officers and men.

[22] Before involving his country in the conflict raging in Europe and across the world, Charles III made provisions to defend the Spanish colonies against the Royal Navy.

De Prado arrived at Havana in February 1761 and began construction efforts to improve the fortifications of the city, although the work was incomplete at the time of the siege.

[24] However, yellow fever had reduced the effective defending forces of the city by the time the siege began to 1,900 regulars, 750 marines, around 5,000 sailors and 2,000 to 3,000 militia, besides several thousand more without muskets or training to operate them.

Detailed plans were made for a combined naval and military attack on Havana, relying on the Royal Navy's superiority in numbers and effectiveness over the Spanish fleet.

Admiral Sir George Pocock, with seven ships-of-the-line and a frigate and Commodore Keppel his second-in-command, was to transport a military force under the command of George Keppel, 3rd Earl of Albemarle to the West Indies, to join the West Indies naval squadron, then under the command of Rear-Admiral Rodney, who was undertaking operations against Martinique, taking on additional troops there.

[29] These plans were modified to meet circumstances, as Rodney and Robert Monckton commanding the troops had captured Martinique before Pocock sailed, 3,000 British and American troops from New York did not arrive at Havana until late July, and the plan to take up to 2,000 slaves from Jamaica to act as pioneers only produced 600 slaves, as many owners were reluctant to part with them without a scheme for compensation.

[30][31] A plan by Amherst to assemble a force of 8,000 men for an attack on Louisiana was dismissed by Albemarle as impractical as it would have left too few troops in the North American colonies.

[38] The combined force now amounted to 21 ships of the line, 24 lesser warships, and 168 other vessels, carrying some 14,000 seamen and marines plus another 3,000 hired sailors and 12,826 regulars.

This last section, more than 200 miles long, would take a large squadron at least one week, and probably several, to complete, giving ample warning for Havana to prepare.

Although the Spanish navigators that charted it thought too dangerous for large warships, it was surveyed by a British frigate, whose captain left parties of his men in the cays to mark the extremities of the channel, allowing the whole fleet to pass through it, safely and undetected.

[41] After surveying the city's defences, the British planned to begin the operations with the reduction of the Morro fortress, on the north side of the channel, through a formal Vauban-style siege.

[42] However, the initial survey had underestimated the strength of the Morro fortress, which was located on a rocky promontory where it was impossible to dig approach trenches and that a large ditch cut into the rock protected the fort on the land side.

[43] Although Prado had received information of the presence of British ships two days before its arrival from a frigate that had escaped from the port of Matanzas, he did not believe that major warships could navigate the Old Bahama Channel.

Firstly, the hurricane season would begin in late August, putting the British fleet in danger: the wet weather starting earlier in that month would probably also initiate an outbreak of yellow fever among the besiegers.

[55] The defence of the Morro was assigned to Luis Vicente de Velasco e Isla, a naval officer, who immediately took measures to prepare and provision the fortress for a siege.

[57] With the arrival of their siege train the next day, the British began erecting batteries among the trees on La Cabaña hill overlooking the Morro (some 7 metres (23 ft) higher) as well as the city and the bay.

Mackellar gradually advanced his breastworks towards the ditch under cover of these batteries so by the end of the month the British had increased their daily direct hits on the Morro to 500.

The next day however British breastworks around the Morro caught fire and the batteries were burned down, destroying the product of much of the work undertaken since mid June.

The debris of the explosion partly filled the ditch but Albemarle judged it passable,[77] and launched an assault, sending 699 picked men against the right bastion.

[80] Artillery batteries were brought up along the north side of the entrance channel from the Morro fort to La Cabaña hill, where they could be trained directly on the town.

[82] A total of 47 guns (15 × 32-pdrs, 32 × 24-pdrs), 10 mortars and 5 howitzers pounded the city from a distance of 500–800 m. By the end of the day Fort la Punta was silenced.

[89][90] In addition, two small frigates or corvettes and two 18-gun sloops, including the Marte commanded by Domingo de Bonechea, and several smaller vessels were captured either along the Cuban coast or in Havana harbour.

The commission placed most of the blame on Prado and Hevia, finding them to have failed to fortify the Cabaña hill properly and to have abandoned it too easily; to have crippled the Spanish fleet by sinking blockships that prevented the remainder taking action against the British and surrendered them intact rather than burning them; they had not mounted any significant counterattacks and, finally, had not removed the royal treasury before the surrender.

The regular garrison of about 3,200 would be backed by a disciplined militia of eight infantry battalions and one regiment each of cavalry and dragoons, totaling 7,500 soldiers, with many of the officers from prominent Cuban families.

[101] Havana and Manila were returned to Spain as a result of the Treaty of Paris signed in February 1763, but the British occupation lasted until two months later, when a newly appointed Captain General of Cuba, Alejandro O'Reilly, arrived to re-establish Spanish rule.