The Sala dei Cento Giorni is a large frescoed gallery or room in the Palazzo della Cancelleria or Chancellery in Central Rome, Italy. The frescoes epitomize the Mannerist style of Giorgio Vasari and his studio.
In March 1546, Cardinal Alessandro Farnese (1520–1589), at the suggestion of Paolo Giovio, commissions Vasari to paint a fresco a hall of the chancery in the Palazzo of San Giorgio, which was remodeled and rebuilt as the massive Palazzo della Cancelleria. The purpose of the frescoes was to celebrate the life of Pope Paul III, Alessandro's grandfather. In his biography of Artists (Vite), Vasari details the planning, commission and execution of this work. Legend has it, that Michelangelo, known for his plodding meticulous style, was shown the work and Vasari bragged about the rapid execution, Michelangelo is reputed to have tartly replied: “si vede!” (“it shows!”). The work even in its day was not admired for its quality. Paolo Giovio reports to Cardinal Farnese that the portraits displeased him. Today, the condition of the frescoes is mediocre, even though they were restored several times after a 1940 fire.
In the Sala dei Cento Giorni, Vasari and his assistants work in an elaborate and fanciful manner. The narrative unfolds within an unusual illusionist space flooded with allegoric ornamentation and further by numerous figures in painted architecture surrounded by simulated sculpture. The gestures and expressions of the figures are extravagant and exaggerated in a courtly manner, according to the Maniera style of the mid-Cinquecento.
The decoration in this room exemplifies the third type of wall decoration: it is stylistically related to the Chamber of Fortune in the Casa Vasari. This hall is rectangular. Its flat wooden ceiling is composed of recessed coffered shapes. These squares are created by the intersection of wooden beams. A corbel resting on the upper part of the wall supports the end of each beam. The east wall contains six large windows on the lower zone and six small ones in the upper zone. The north and south walls each contain only one bay, while the west wall contains two. The treatment of the wall decoration is geometric and architectonic. The wall is not considered as a painted two-dimensional surface, but rather as a plastic, architectural structure in which imaginary and real space can expand and contract as one.