Giovanni Battista Comerio (1593-1667) was a gilding craftsman, with a shop in Via Santa Maria Segreta, in front of the church of the same name. In his will of 1664 he nominated the Maggiore Hospital his heir, asking in exchange, given his precarious health conditions, that he be granted board and lodging by the hospital. He died four years later in the house he had been given and also left the furniture to the Pious place. The portrait is commissioned from Cesare Fiori, who will go on to make two more portraits for the Quadreria. This painter, of whimsical character (he was fencer, dancer and standard bearer of the urban militia) and a multifaceted artist (he also works as an architect, engraver and medalist and founded the second Ambrosian Academy) was a pupil of Carlo Cane and teacher of Andrea Porta.