The sitter was a Bolognese of noble family. The writing on the letter identifies the sitter as Bartolomeo Bianchini of Bologna ('Bononiae'), the city where Francia worked as a painter and goldsmith. Bianchini was a humanist scholar of noble family; he was esteemed by his contemporaries but left few writings (e.g. 'Vita di Codro', 1502). He was alive in 1497 and died before 1528. He commissioned other works from the artist and there is evidence that he was friendly with Francia. The painting is likely to date from the 1490s.
The National Gallery, Trafalgar Square, London WC2N 5DN