During the American Revolution Spain supported the American cause with supplies. They were was also at war with Britain at the time and engaged in battles around the world, including America. Regimiento de Infantería de Ultonia nº 59 is a Spanish infantry regiment that fought in America. Battles included Fort Bute (1779), Baton Rouge (1779), 2nd Battle of Savannah (1779), Fort Charlotte (1780), and the Siege of Pensacola (1781).
Source(s): http://peter.mackenzie.org/history/hist51.htm, Image: Durero (wikipedia),