A portrait drawing of Katherine, fourth wife of Charles Brandon, Duke of Suffolk on paper prepared with a pink ground. She is shown bust length, facing three-quarters to the left, wearing an English hood and a collar embroidered in black. A pendant worn by the duchess has been lightly sketched and the jewelled pattern of her hood has been summarily indicated. The drawing is in black and coloured chalks with black ink on the sitter's face, headdress and collar. 

The drawing is inscribed damast (damask) at the bottom and rot (red) on the band of the hood in Holbein's hand. An eighteenth-century inscription (a copy of a mid-sixteenth-century original) at top left identifies the sitter as 'The Dutchess of Suffolk'.

Katherine was the daughter and heir of William Willoughby, Baron Willoughby de Eresby, and his Spanish wife Maria de Salinas, who probably travelled to England with Katherine of Aragon in 1501. Her father died in 1526, and Katherine inherited his extensive Lincolnshire estates. In 1529 she became the ward of Charles Brandon, Duke of Suffolk, who sought to expand his East Anglian power base through her inheritance. To this end, Brandon married Katherine as his fourth wife in 1533. She became the mother of his two sons Henry and Charles, both of whom were the subject of portrait miniatures by Holbein (RCIN 422294 and RCIN 422295). The miniatures are dated 1541 and this drawing may have been made in the same year, when Katherine was 22 years old. It is possible that it was also preparatory for a miniature.