Florentine poet and writer
Source (Wikipedia): Giovanni della Casa

Giovanni della Casa was an Italian poet, diplomat, clergyman and inquisitor, and writer on etiquette and society. He is celebrated for his famous treatise on polite behavior, Il Galateo overo de’ costumi (1558). From the time of its publication, this courtesy book has enjoyed enormous success and influence. In the eighteenth century, influential critic Giuseppe Baretti wrote in The Italian Library (1757), “The little treatise is looked upon by many Italians as the most elegant thing, as to stile, that we have in our language.”