Juan Jose was the son of King Philip IV of Spain. He received the princely education and a large income obtained his first military command in 1647 when he was sent to Naples to crush an uprising, which he is discussing here. It would seem that the restoration of Royal authority was due rather to the exhaustion of the insurgents and the follies of their French leader, Henry the Duke of Guise, than to the forces of Don Juan. He served as Prime Minister for Spain between 1677 and 1679.