Though funds for the chapel were assembled in 1429 by Andrea Pazzi, head of the Pazzi family, whose wealth was second only to the Medici, construction did not begin until about 1442. The chapel was completed in 1443. The building is considered to be an Early Renaissance masterpiece. The main purpose of the building was the cathedral chapter house and use as a classroom for the teaching of monks and other religious purposes. There was also a chapel behind the altar where the commissioning family had the right to bury its dead. The Pazzi's ulterior motive in building the chapel was probably to make their mark on the city ofFlorence and to emphasize their wealth and power. The fact that the city was at war with a neighboring city at the time and still acquired the funds to build this chapel showed the importance it had to the Pazzi family and the people of Florence. Formerly considered a work of Filippo Brunelleschi, it is now thought that he was responsible for the plan, which is based on simple geometrical forms, the square and the circle, but not for the building's execution and detailing. A façade that he had begun, and of which only the lower register can be seen, was partially obscured by the addition of a porch. The main inspiration for this piece was the Dominican monastery of Santa Maria Novella, also located in Florence. The size of the chapel was predetermined by existing walls, creating an unusual situation, however, where the space was not square as in the Old Sacristy, which was the model for this building, but rectangular and transept-like and thus in contradistinction to the square, axially-placed altar. Despite this, and its complex history, the building gives us insight into the ambitions of Renaissance architects in their struggle to bring coherence to the architectural language of columns, pilasters, arches and vaults. Between the pilasters in the transept there are tall, blank, round headed panels and, above them, roundels, common Renaissance decorative motifs. The architectural elements of the interior are all in pietra serena, a high quality, fine grained sandstone. The load-bearing structure of this building is its masonry, i.e. it is the walls that support the arches and domes, not the pilasters which are decorative rather than structural. As to the architect, scholars argue that it is not actually by Brunelleschi. No period sources nor period documents support this theory, with the first written mention of Brunelleschi as the architect first appearing with an anonymous author who wrote in the 1490s. The most common proof given for crediting Brunelleschi is the Pazzi Chapel's clear similarity to the Old Sacristy; others argue that his style had developed in the twenty year interim and that the Pazzi Chapel would represent a retrograde step. Scholars now consider the chapel as possibly the work of Giuliano da Maiano or Michelozzo. The tondi of the seated Apostles are by Luca della Robbia, who also did the terracotta decorations in the cupola of the porch. It has been suggested that the roundels of the Evangelists may have been the work of Donatello.
