(b. 1280/85, Siena, d. 1344, Avignon)
Equestrian Portrait of Guidoriccio da Foglianoc. 1330
Palazzo Pubblico, Siena
The fresco of Guidoriccio da Fogliano, depicting the conquest of the castles of Montemassi and Sassoforte in 1328, formed part of a fresco cycle "Castelli" which occupied the upper part of the wall opposite to the Maestà in the Sala del Mappamondo. The cycle, commemorating the castles conquered by the Sienese, was initiated in 1314 by the representation of the Castle of Giuncarico, it was continued by the Guidoriccio and in 1331 by the Castles of Arcidosso and Piano. The latter were destroyed in 1361 when Lippo Vanni painted the Battles of Valdichiana and Poggio Imperiale.
In the 1970s, the famous fresco, which had always been, considered the greatest example of Martini's artistic excellence, was re-attributed to a much later artist. The controversy that followed this re-attribution, further stimulated by the discovery of a fresco below the Guidoriccio (a very beautiful one, and certainly much older as we can see from the overlapping of the intonaco), turned into an animated diatribe that has not yet been placated.