On this date in 1345, Giovanni Martinozzi died for the faith in Cairo.
Martinozzi was a Franciscan who hailed from one of the prominent families of Siena. Like the famous founder of his order, Martinozzi undertook to convert the Saracens: part of a mmissionary ovement of Franciscans abroad from Europe which had been encouraged by the papacy as a means to discharge the troublesome ferment of the Franciscan movement. (As a reference point, Martinozzi would have died in the generation following the events of The Name of the Rose.)
After re-converting a Genoese merchant who had apostatized to Islam, Martinozzi was tortured and on April 15, 1345, immolated along with the inconstant entrepreneur.
According to S. Maureen Burke (“The ‘Martyrdom of the Franciscans’ by Ambrogio Lorenzetti”, Zeitschrift für Kunstgeschichte, 65 Bd., H. 4 (2002)), a fresco of Beato Martinozzi’s martyrdom once adorned the Basilica of San Francesco in Siena; the fresco either does not survive or has eluded my online peregrinations. Giotto’s thematically topical 1320s Ordeal by Fire before the Sultan of Egypt will have to serve: it alludes to an episode (perhaps apocryphal) during Saint Francis’s travels in Egypt a century before.