Philip IV of Spain (r. 1621–1665) was known as the ‘Planet King’, shining brightly in the universe of the arts even if the Golden Age of Spanish painting coincided with imperial decline. The Buen Retiro Palace surpassed any palace ever built in Europe for the collection of paintings it contained, most of them commissioned in the 1630s from the finest painters in Europe at the time—Velázquez and Zurbarán, Rubens, Claude, Poussin, Jan Both, Herman van Swaneveld, Domenichino, Lanfranco and others.