Inspired by the Spanish court during his time as Ambassador of the Holy See (1524–1529),[1] Castiglione set the narrative of the book in his years as a courtier in the Duchy of Urbino.

[3] The book portrays the small courts of the High Renaissance which were vanishing in the Italian Wars — with a reverent tribute to the friends of Castiglione's youth.

It pays tribute in particular to the chastely married Duchess Elisabetta Gonzaga of Urbino, to whom Castiglione had addressed a sequence of Platonic sonnets, and who died in 1526.

The book is organized as a series of conversations supposed to have taken place over four nights in 1507 between the courtiers of the Duchy of Urbino, at a time when Castiglione was himself a member of the Duke's Court (although he is not portrayed as one of the interlocutors).

The nature of an ideal courtier is debated between the many characters on the basis of various qualities, such as the need for noble rank, physical prowess, modesty, and pleasant physique, among other attributes.

The ideal courtier is described as having a cool mind, a good voice (with beautiful, elegant and brave words) along with proper bearing and gestures.

[5] The Courtier enjoyed influence for some generations, not least in Elizabethan England following its first translation by Sir Thomas Hoby in 1561, a time when Italian culture was very much in fashion.

Wayne Rebhorn, a Castiglione scholar, states that the courtier's speech and behavior in general is "designed to make people marvel at him, to transform himself into a beautiful spectacle for others to contemplate.

In Book I, the Count states that when the courtier speaks he must have a "sonorous, clear, sweet and well sounding" voice that is neither too effeminate nor too rough and be "tempered by a calm face and with a play of the eyes that shall give an effect of grace" (Castiglione 1.33).

The Count reasons that by obscuring his knowledge of letters, the courtier gives the appearance that his "orations were composed very simply" as if they sprang up from "nature and truth [rather] than from study and art" (1.26).

Robert J. Graham, a Renaissance literary scholar, notes that "questions of whose language is privileged at any given historical moment are deeply implicated in matters of personal, social and cultural significance",[11] which he states is the primary reason for Castiglione's usage of the native vernacular.