While Spain refused to become formally involved in the American Revolutionary War, they allowed goods to be shipped through Louisiana, avoiding the British blockade while their recapture of Florida denied the Royal Navy bases on the Gulf Coast.

British West Florida was strategically important, since it controlled entry to the Mississippi River through the port of Mobile and included the modern Gulf Coast of the United States.

This support was provided unofficially since Spain's Chief Minister, Count Floridablanca, hoped diplomacy would persuade Britain to return Menorca, Gibraltar and the Floridas and remove illegal settlements in Central America.

In return, France would assist in recovering Gibraltar, Menorca and Florida, but Spain would only attack British possessions outside the United States and did not recognise US independence until the Peace of Paris in 1783.

[5] One reason for their reluctance to intervene directly was that Charles III and Floridablanca were concerned by the potential impact of the American Revolution on Spain's own colonies, which they considered essential for modernising and expanding the Spanish economy.

[10] When Yorktown surrendered in October 1781, Britain accepted defeat in North America, but inflicted heavy casualties on the French fleet at the Battle of the Saintes in April 1782.

[11] Spain insisted on continuing the war until Gibraltar fell, as stipulated by the Treaty but withdrew that requirement after the disastrous repulse of a combined French and Spanish assault in September 1782.

[14] Divisions between their opponents allowed them to negotiate separately with each to improve their overall position; they agreed preliminary terms with the United States in September 1782, leaving France and Spain isolated.