John Joseph of Austria (; 7 April 1629 – 17 September 1679), also called John the Younger was a Spanish general and political figure. He was the only illegitimate son of Philip IV of Spain to be acknowledged by the King and trained for military command and political administration.
Don John advanced the causes of the Spanish Crown militarily and diplomatically during the century's crisis, recovering control of Naples, Sicily and Catalonia from local revolts, although failing to advance from only initial victories against France and England in his stint as governor of the Spanish Netherlands from 1656 to 1659. He then failed to quell the revolt of Portugal, which separated from Spain.
After his military career, he returned to the court, where his opposition his father's widow, Queen Mariana of Austria, led to a 1677 palace coup through which he exiled Mariana and took control of the monarchy over his young half-brother Charles II of Spain. Don John worked to secure Charles II's international position against the ambitions of Louis XIV of France, although his labour was left unfinished with his death in 1679.
Early life
thumb|Coat of arms of John of Austria the Younger
His mother was María "La Calderona" Calderón, a popular actress, who was forced into a convent shortly after his birth. He was raised in León by a woman of modest circumstances who likely did not know his parentage, though he received "a careful education" at Ocaña (Kingdom of Toledo). In 1642, the King recognized him officially as his son, creating him a prince (Serenity) and John began his life's career as a military representative of his father's interests.
Military career
Don John was sent in 1647 to Naples, then in the throes of the popular rising first led by Masaniello, with a naval squadron and a military force, to support the viceroy. He ordered his land and sea forces to blockade the rebel held city while Rodrigo Ponce de León, 4th Duke of Arcos inserted agents. Don John waited until the exhaustion of the insurgents and the follies of their French leader, Henry II, Duke of Guise allowed him to move in and crush the remains of the revolt and drive out the, by then, despised French.
thumb|left|upright|The young Don John as general of the Spanish army by [[Jusepe de Ribera]]
He was next sent as viceroy to Sicily, whence he was recalled in 1651 to complete the pacification of the Principality of Catalonia, which had been in revolt since 1640. On the way to Catalonia to assume his position, he captured the French galleon Lion Couronné, with a squadron of galleys he had under his command. The high-handedness of the French, whom the Catalans had called in to help their revolt, had produced a reaction, and many switched their loyalties back to the Spanish King. By the time Don John assumed command, most of Catalonia had been recovered and he had not much more to do than to preside over the final siege of Barcelona and the convention which terminated the revolt in October 1652. on 17 September 1679.