Philip III was King of Spain and Portugal during the period known as the Iberian Union, reigning from 1598 until his death in 1621. He was also King of Naples and Sicily, Duke of Milan, and Lord of the Seventeen Provinces. A member of the House of Habsburg, he was born in Madrid to King Philip II of Spain and his fourth wife, Anna of Austria. The family was heavily inbred; Philip II and Anna were uncle and niece, as well as cousins. From Wikipedia