Spain in the American Revolution.

Spain took possession of the "Louisiana Territory" from France in 1769, and
declared war on England on 8 May 1779. Governor/General B. Galvez in New
Orleans pushed the English out of St. Louis, MO, Baton Rouge, LA and Mobile,
AL then, with 8,000 troops besieged and defeated the British army in
Pensacola, FL In 1781. These campaigns required Spanish military units from
the mainland ("Metropolitan" units), from Louisiana militias, especially
the "Louisiana Battalion of Infantry", and colonial units from Cuba, Mexico,
and elsewhere. Thus some Mexicans became "Sons of the American Revolution".
There were many naval units and ships also engaged for transport and cover.
At the end of the war Spain regained East and West Florida.

Ref: "The Spanish Army in North America 1700 - 1793" by Rene Chartrand,
Osprey Publishing, 2011

And "The Galvez Expedition, 1779 - 1883 Officers and Soldiers Serving under
Gen. Bernardo de Galvez" by Robert C. Churchill ( a very rare book)