Greetings,
Well, it would be a question of digging up some records and finding people who knew the family. I don't know the names of the general's parents but i think he was born at Placetas.
Looking at the Diccionario Biografico Remediano and at Hilda Pomares' pages i see there were quite a few Monteagudos at or near Remedios, back in the 1700s. There may have a few lines in the XIX century.
Juan