Begun with operations against British positions on the Mississippi River shortly after Britain and Spain went to war in 1779, Gálvez completed the conquest of West Florida in 1781 with the successful siege of Pensacola.

[1] When Bernardo de Gálvez, the colonial Governor of Spanish Louisiana, received word of this on 21 July, he immediately began to secretly plan offensive operations.

[3] On August 27, Gálvez set out by land toward Baton Rouge, leading a force that consisted of 520 regulars (about two-thirds of them recent recruits), 60 militiamen, 80 free blacks and mulattoes, and ten Anglo-American volunteers headed by Oliver Pollock.

[6] When Gálvez arrived at Baton Rouge on 12 September, he found Fort New Richmond garrisoned by over 400 regular army troops and 150 militia, under the overall command of Lt.

In early 1780, Gálvez embarked on an expedition to capture Mobile, which was one of only two major British military establishments left in West Florida; the other was the capital, Pensacola.

Gálvez in the fall of 1780 sought to capture Pensacola, launching his naval force from Mobile, but the fleet was dispersed by a major hurricane.

A lucky cannon shot hit the powder magazine in one of the outer defenses on 8 May, and the Spanish quickly capitalized upon this development by capturing the British position.