<P> The most pressing issue in the war with Spain was a threatened invasion of Portugal . Portugal, although a historic British ally, had remained neutral through most of the conflict . By early 1762 they were drawn into the war with the First Cevallos expedition and became a likely target of Spain . Portugal's long border with Spain was considered vulnerable and easy to overrun, rather than the more complex efforts a siege of the British fortress of Gibraltar would require . Spanish forces began massing on the Portuguese border, ready to strike . Britain moved swiftly to support their Portuguese allies, shipping in supplies and officers to help co-ordinate the defence . </P> <P> The original Spanish plan was to take Almeida and then to advance towards the Alentejo and Lisbon, but they switched their target to Porto as it would strike more directly at British commerce . Under the direction of the Marquis of Sarria Spanish troops crossed from Galicia into northern Portugal capturing several towns . However, the thrust against Porto stalled in difficult terrain and due to the flooding of the River Esla . British troops began arriving that summer with 6,000 coming from Belle Île under Lord Loudoun and a further 2,000 from Ireland . Spain invested and captured the border fortress of Almeida . A British - Portuguese counter-attack led by John Burgoyne captured the Spanish town Valencia de Alcántara . French forces began to arrive to support the Spaniards, but like their allies they began to suffer high levels of attrition through disease and desertion . In November with problems with their lines of supply and communication the Bourbon allies withdrew and sued for peace . Despite the large numbers of forces involved, there had been no major battles . </P> <P> In June 1762 British forces from the West Indies landed on the island of Cuba and laid siege to Havana . Although they arrived at the height of the fever season, and previous expeditions against tropical Spanish fortresses failed due, in no small part, to tropical disease, the British government was optimistic of victory--if the troops could catch the Spanish off - guard before they had time to respond . The British commander Albermale ordered a tunnel to be dug by his sappers so a mine could be planted under the walls of the city's fortress . British troops began to fall from disease at an alarming rate, but they were boosted by the arrival of 4,000 reinforcements from America . On 30 July Albermale ordered the mine to be detonated, and his troops stormed the fortress . </P> <P> With Havana now in their hands, the British lay poised to strike at other targets in the Spanish Main should the war continue for another year . However, they had suffered 1,800 deaths and more than 4,000 casualties during the siege--almost entirely from disease--and for the moment set about consolidating their hold on the countryside around Havana . During the year of British occupation, commerce in Havana boomed, as the port was opened up to trade with the British Empire rather than the restricted monopoly with Cadiz that had existed before . </P>

What advantage did the british have over the patriots at the beginning of the war