The shifting power relations among the numerous Italian city-states fostered the rise of princely courts and control of cities by despots during the 15th Century. Princely courts emerged as cultural and artistic centers. Their patronage contributed to the formation and character of Renaissance art. The artistic and architectural holdings of such princely rulers were emulated by wealthy individuals throughout Europe.
Similarly, the courts of aristocratic Italian Renaissance nobility of the Medici, Gonzaga, Este, and Sforza families competed to outshine each other. The leading Florentine family was the Medici. The Medici spent money on constructing churches, encouraging art and supporting charities. One of the Medici Popes, Leo X, was a notable patron of the arts in Rome. These families were patrons of the arts during the early Renaissance. There were two main systems of patronage in Renaissance Italy.
A rich person could take an artist into his or her household and in return the artist would supply the patron artistic needs, or someone or some organization could commission a single work from an artist and employ him until that work was finished client. If the commissioned work was particularly complicated the artist could be on the client payroll for years. Other ways for acquiring works of art are, choose work that had already been completed, or buy one from a previous owner. Patronage could be collective or individual. There are some famous examples of group patronage in Florence.
For example, the wool guild was responsible for the Cathedral and gave out many important commissions for religious works. Another kind of collective patron, was the religious confraternity, e. g. The commission of The Virgin of the Rocks by Leonardo. Leonardo, the oldest of the three major High Renaissance artists, worked for much of his career under court patronage. Other types of patronage are city states (e. g. Bronze David by Michelangelo), and prince from a state (Leonardo was court painter for the Duke of Milan for 17 years).
These commissioned artists always seemed to characterize or paint in the new Renaissance style or spirit, which is known as humanism. Humanism was the basic concept of the Italian Renaissance. It is the term used to define that philosophical movement in Italy at the end of the 14th century and during the 15th and 16th centuries which asserted the right of the individual to the use of his own reason and belief, and stressed the importance and potential of man as an individual.
The rise of Humanism can be seen in paintings created by Renaissance artists. During the Middle Ages, saints in paintings wore halos (a ring or circle of light) around their heads. Artists also used hieratic scale in paintings during the Middle Ages, making saints or members of the family of God larger in scale than ordinary or less important figures. As Humanism became more popular during the Renaissance, ordinary people grew to be the same size as saints in paintings