Béatrice de Cusance was the daughter of Claude-François de Cusance, baron of Belvoir in Franche-Comté, a region in modern France which at that time was owned by the Spanish Hapsburgs. A celebrated beauty, this portrait was probably painted in Brussels early in 1635, the same year Béatrice de Cusance married the Prince of Cantecroix, who was to die only two years later. She subsequently married Charles IV, Duke of Lorraine and had three children. Pentimenti reveal that the Princess was first painted wearing a wired standing collar known as a rebato which rises at the back of the neck but that the artist changed this to a falling band of lace. Her black over-gown is worn over a bodice and skirt of pale grey coloured silk brocaded in gold, a fashionable style of dress deriving from the Netherlands. She wears pearls at her wrists, neck and ears and her bodice is also trimmed with a string of pearls.