 Argüelles Sr. was the first "Alcalde" (Mayor) of San Agustín, and had been in charge of munitions in the Florida forts of Santa María, San Agustín (now St. Augustine), and Santa Elena.Martín Argüelles Jr. served the Spanish crown in Portugal and several garrisons and expeditions which embarked in the Spanish Armada which went in search of corsair Francis Drake.He was later transferred in 1594 from Havana, Cuba, to Mérida, Mexico, where he was appointed Executive Officer of the Mérida fortress and coast.