Early in 1780, the British garrison of Fort Charlotte at Mobile numbered more than 300 men, in addition to Artillerymen, Engineers, 21 Artificers and at least 56 Sailors, the garrison included troops from the following units:

4/60th Foot 4 Companies
United Provincial Corps of Pennsylvania and Maryland Loyalists (16 men)
Captain Walker's "Provincial Dragoons"
Captain Ree's Militia

( The last two units were part of a total of 52 local "volunteers", 15 of whom deserted during the siege. )

The garrison was under the command of Captain Elias Durnford, sometime Lieutenant Governor of the province. Besides the fighting men mentioned above, there were 55 non-combatants in the fort, including a chaplain, a commissary, a surgeon's mate and 52 negro servants ( these negroes may have been armed ) and workmen. Among Captain Durnford's 12 officers were Lieutenants Loup and Macdonald of the 4/60th Foot.

In a letter dated the 14th March 1780, Durnford informed Campbell that he had surrendered the garrison to Galvez , he reported that the number of killed, wounded and prisoners was 304.

With the capture of Mobile, Galvez made two slightly different lists of the prisoners that he had taken there.

In his Diary of the Expedition against Pensacola and Mobile.., he lists 285 prisoners made up of;

1 Captain, 2 Lieutenants, 2 Ensigns, 15 Sergeants and 78 Privates of the 60th Foot.
1 Sergeant, 1 Corporal, 2 Privates, 15 Artillerymen, and 1 Armourer of the "Maryland Corps.
Plus 2 Surgeons, 60 Sailors, 54 Habitants, and 51 Negroes.

On the 20th March 1780, Galvez made another list in which he reported 307 prisoners; 13 Officers, 113 Privates, 56 Sailors, 70 Hunters and Habitants, and 55 Armed Negroes.

Sources

The Spanish Conquest of British West Florida 1779-1781, by A. W. Haarman, pub. Florida Historical Quarterly, Vol. XXXIX, pp.107-134.
Colonial Mobile, by P. J. Hamilton, pub. Boston & New York, 1910.
Memoir of Major Patrick Murray, edited by Lewis Butler, in The Annals of the King's Royal Rifle Corps, Vol. I, pp.288-319, London 1913.
Bernardo de Galvez in Louisiana 1776-1783, by J. W. Caughey, Berkeley, Calif., 1934, pp.184 & n.33.
The Surrender of Ft. Charlotte, Mobile 1780, by William Beer, pub. American Historical Review, Vol. I, No.4, pp.699.

More Spanish and British Units: American Revolution

1st Note: British at Pensacola
2nd Note: Spanish in Louisiana
3rd Note: Spanish at St. Louis
4th Note: British at Mobile
5th Note: Spanish at Mobile
6th Note: British Attack St. Louis
7th Note: Spanish Garrison of St. Louis
8th Note: Spanish "Regular" units in Louisiana and West Florida