Isabella d’Este, Marchioness of Mantua, sister of Beatrice d’Este (who married Ludovico Sforza in 1491) and one of the family of the Lords of Ferrara, Modena and Reggio, was a brilliant and cultured woman and one of the greatest patrons of the arts of her time.

This portrait cartoon of her, which survives in fragile condition, appears not to have been used, despite the fact that the contours of the drawing have been pricked for transfer. This would seem to imply that Leonardo planned to paint Isabella’s portrait, but for some reason he does not appear to have executed her portrait painting.

Isabella’s interest in portrait paintings is apparent in a letter of 1498 to Cecilia Gallerani, requesting Leonardo’s portrait of her which she wishes to compare with a portrait by Giovanni Bellini, who was the most famous Venetian artist of his time. It is likely that Leonardo drew Isabella’s portrait from life, perhaps during a visit to Mantua early in 1500, when on his way to Venice from Milan.

The cartoon is damaged and cut down at the base and a copy now in the Ashmolean Museum, Oxford, indicates that both of the sitter’s hands were originally included, shown resting on a stone parapet at the base of the painting. The strict profile of Isabella’s face runs contrary to the turn of her body and is untypical of Leonardo’s other portraits in which he seeks to stimulate emotional engagement between viewer and sitter.

The classicising profile of Isabella’s portrait may be a requirement of decorum, in light of her regal status, and an indication of her interest in the collection of classical coins and antique cameos, on which profile portraits are commonly found.