[4] Folch studied mathematics and engineering at the Royal Military Academy of Barcelona[3] and on April 23, 1771, he was commissioned a sublieutenant in the 2nd Regiment of Light Infantry of Catalonia in the Spanish army.
[3] In August 1793, Folch was assigned a naval expedition to map the central part of the west coast of the province of East Florida, the area around Tampa Bay.
After successfully completing this arduous task, the governor of Louisiana, Baron Carondelet, appointed him to command two small vessels that he had outfitted to patrol the coast near the mouth of the Mississippi River.
He sent a troop of 150 soldiers from Pensacola to suppress the revolt; they arrived in September,[15] and defeated the insurrectionists, who had failed to gain the support of local Anglo-American settlers, most of whom were satisfied with Spanish rule.
[16] Folch was promoted to brigadier in 1810, and replaced by his son-in-law Francisco Maximiliano Saint Maxent La Roche[17] in March 1811 as governor of West Florida.