Calcio Fiorentino was an early form of football that originated in 16th century Italy. The Piazza Santa Croce of Florence is the cradle of this sport, that became known as giuoco del calcio fiorentino ("Florentine kick game") or simply calcio ("kick").

The official rules of calcio were published for the first time in 1580 by Giovanni de' Bardi, a Florentine count. Just like Roman harpastum, it was played in teams of 27, using both feet and hands. Goals could be scored by throwing the ball over a designated spot on the perimeter of the field. The playing field is a giant sand pit with a goal running the width of each end. There is a main referee, six linesmen and a field master. Each game is played out for 50 minutes with the winner being the team with the most points or 'cacce'.

Originally, calcio was reserved for rich aristocrats, who played every night between Epiphany and Lent. In the Vatican, even Popes, such as Clement VII, Leo XI and Urban VIII were known to play.

The sport was not played for around two hundred years but then revived in the twentieth century when organized games began again in 1930. Today, three matches are played each year in Piazza Santa Croce, in the 3rd week of June. The modern version allows tactics such as head-butting, punching, elbowing, and choking, but forbids sucker-punching and kicks to the head.