In an appendix to his biography of Francesco Guicciardini published in 1862, Eugène Benoist printed a brief piece by Guicciardini which the editors of Guicciardini's Opere Inedite had overlooked. The piece is a ‘Portrait of Lorenzo Magnifico de' Medici’. About its authenticity there can be no doubt; the manuscript on which Benoist's publication was based, was written in Guicciardini's own hand. Thus Palmarocchi, the editor of the most recent critical edition of Guicciardini's works, printed it in the volume containing Guicciardini's Saitti Politici e Ricordi. In an explanatory note Palmarocchi tried to date the manuscript and suggested that it was written in Spain during the last months of the year 1512 and the first of 1513.