George III. entrusted the Duke of Cumberland with the task of selecting the chiefs who were to be placed at the head of the enterprise, and his choice fell upon the following: Lieutenant-General Keppel, Earl of Albemarle, for general-in-chief of the land forces, and Admiral Sir George Pococke for the command of the squadron. The latter and a division of four thousand men gathered in Portsmouth and orders were given to General Monckton to hold the forces which had gone to the conquest of Martinique and Guadeloupe ready for the arrival of Admiral Pococke. The authorities in Jamaica and the British colonies of North America were ordered to prepare two divisions, the first of two thousand men, the latter of four thousand. The British command staked everything upon a surprise attack. Fear that information of the rupture between the two countries might have reached Cuba, caused no little anxiety to Lord Albemarle and Admiral Pococke. The expedition narrowly escaped an encounter with the squadron of M. de Blenac, who had left Brest in aid of Martinique with seven vessels and four frigates and a sufficient force to have saved that colony, had he come in time. Unfortunately he arrived in sight of Martinique only after the surrender of Fort Royal, and on hearing that the island was in possession of the British, he altered his course and turned towards Cape France, leaving the passage free for Admiral Pococke and his fleet.
Upon his arrival in Martinique, Lord Albemarle took command of all the forces assembled on the island and found that his army consisted of twelve thousand men. He divided them into five brigades and formed besides them two bodies, one of four companies of light infantry brought from England, and one battalion of grenadiers under the command of Colonel Guy Carleton, and placed two other battalions of grenadiers under the command of William Howe. He also ordered the purchase of four thousand negroes in Martinique and other islands, who were incorporated into a company with six thousand negroes of Jamaica. When all these preparations had been made, the forces that were to take part in the siege of Havana were under orders of the following commanders:
Lieutenant-General George August Eliot, second chief.