late 15th- and early 16th-century part song performed in Florence during the carnival season. The Florentines celebrated not only the pre-Lenten revelry but also the Calendimaggio, which began on May 1 and ended with the Feast of St. John on June 24. An essential part of the festivities was the singing and dancing of secular songs by masked merrymakers. Under Lorenzo de' Medici (Medici, Lorenzo de') (ruled 1469–92) the carnival celebrations became more intense and elaborate, and, as a result of his leadership and encouragement, the court also took a more active part. Lorenzo himself wrote poems to be sung by his courtiers as well as by guild members, the former performing songs based on stories taken from mythology and the latter basing their repertoire on subjects of a more current and popular appeal.

Textually, the canti carnascialeschi descend from the old cacce, which were also topical, descriptive, and full of double meanings. Often, these are satirical or obscene in character, and the titles of the songs themselves effectively portray the vigour and excitement of life in 15th-century Florence. Musically, the pieces are chordal and strophic, in a style similar to the Mantuan frottole, this form probably emanating from the outdoor and public nature of the performances. (They included serenades, chariot songs, and processionals, for example.) In many instances, the music is in an ABBC form, with the ⁴/₄ metre changing to ³/₄ on the C section; this is then repeated for a number of stanzas. A number of carnival songs were written by Heinrich Isaac during his stay at Lorenzo's court (c. 1480), but, unfortunately, they have been lost.

The fall of the Medici (1494) and the rule of Savonarola strongly affected the carnival songs, many of which disappeared along with art treasures and musical instruments. Some of the better known melodies survived, however, newly adorned with sacred and penitential texts. After the fall of Savonarola in 1498, the carnival was reinstated, but it never regained its original colourfulness and air of joyful gaiety. Instead, it became a sombre and dignified court ceremonial, and, as a result, the canti carnascialeschi lost their popular spontaneity and grew more literary in nature.