Juan José de Austria (born April 7, 1629, Madrid, Spain—died September 17, 1679, Madrid) was the most famous of the illegitimate children of King Philip IV of Spain. He served with some success as a Spanish military commander and from 1677 until his death was chief minister to King Charles II.
Juan José was the son of King Philip IV of Spain and María Calderón, a celebrated actress. He received a princely education and a large income and obtained his first military command in 1647, when he was sent to the Spanish-ruled kingdom of Naples to crush a popular uprising. In 1651 he led the royal forces besieging Barcelona, capital of the rebellious province of Catalonia, and negotiated the terms for its surrender (October 1652). From 1656 to 1658, as governor of the Netherlands, he enjoyed varying success as a military commander. Recalled to campaign against the rebellious Portuguese, he was initially victorious but was ultimately defeated at Amexial (June 8, 1663) and relieved of his command. His offensive intimation of his ambition to succeed his father scandalized the king, and he was out of favour at the time of Philip’s death in September 1665.
Juan José played an active part in the political intrigues that marked the minority of the feeble new king, his half brother, Charles II. In 1669 he headed a military uprising that forced the queen regent, Mariana, to dismiss her favourite and confessor, Father John Nithard. In early 1677, he drove Mariana and her new favourite, Fernando de Valenzuela, from court and established himself as first minister.
Although highly popular and widely regarded as the saviour of his country, the arrogant and paranoid Juan José soon lost support by his intrigues and his attempts to advance his own prestige at the expense of the compelling needs of the public. During his tenure the Treaty of Nijmegen was signed with France (1678), which resulted in territorial losses and marked a further decline in Spain’s international standing. Shortly before his death, Juan José arranged the ill-fated marriage of Charles II to Marie-Louise of Orléans, niece of the French king Louis XIV, but when he died Juan José’s influence was declining, and his reputation badly tarnished.