Baldassare Castiglione (Italian: [baldas'sa?re kasti?'?o?ne]; December 6, 1478 – February 2, 1529), count of Casatico, was an Italian courtier, diplomat, soldier and a prominent Renaissance author, who is probably most famous for his authorship of Il Cortegiano or The Book of the Courtier.
The work was an example of a courtesy book, dealing with questions of the etiquette and morality of the courtier, and was very influential in 16th-century European court circles.