This grandiose structure was the seat of the General Council of the Florentine Republic. It was built in 1495 and was to be decorated with frescoes by Leonardo and Michelangelo.

We still possess some of the preliminary studies for these frescoes which were never made. Giorgio Vasari took over the decoration work and, between 1563 and 1565, transformed the hall into an enormous pictorial celebration of Cosimo de' Medici who was Duke of Florence and Siena after 1557.
On the wall in front of the Udienza, in the niche, there is a marble group of the Genius of Victory sculpted by Michelangelo between 1532 and 1534.