Philip IV of Spain (; 8 April 1605 – 17 September 1665) was King of Spain (as Philip IV in Castille and Philip III in Aragon) and Portugal as Philip III . He ascended the thrones in 1621 and reigned in Spain until his death and in Portugal until 1640. Philip is remembered for his patronage of the arts, including such artists as Diego Velázquez, and his rule over Spain during the challenging period of the Thirty Years' War.