Don Gaspar de Guzmán (1587–1645), Graf-Herzog von Olivares

In the 1630s the man on this horse effectively ran Spain. Gaspar de Guzmán, the Count-Duke of Olivares, was the chief minister of King Philip the Fourth, and for two decades he held more real power than almost anyone at court. The portrait is a smaller version of a huge equestrian picture by Diego Velázquez, the king's painter, reworked here by Velázquez's pupil and son-in-law Juan Bautista Martínez del Mazo. Reductions like this were how a court projected authority, sent out and hung in other households to keep the minister's image in circulation. He wears full armour and holds a commander's baton, turned in the saddle as though reviewing troops just out of frame.