Question: Il promo d'oro marked the wedding between Leopold I and what relation of Kind Philip IV?
Sentence (from "Equestrian Portrait of Philip IV"): The Equestrian Portrait of Philip IV was a portrait of Philip IV of Spain on horseback, painted by Velázquez in 1635-36 as part of a series of equestrian portraits for the Salón de Reinos at the palacio del Buen Retiro in Madrid (a series that also included that of Philip's son prince Balthasar Charles).
Relevant evidence: No