The name of Giovanni Rucellai, the wonderful "sponsor" - as one might say today - of the facade of Santa Maria Novella, is written in huge letters on the pediment above the basilica, followed by the date of its completion (1470). The date of the beginning of work is less certain, but it was probably not before 1458. The idea itself dates back to the Council of Florence (1439-1442), whose committees met in Santa Maria Novella and were presided over by Pope Eugenius IV and subsequently by the young Leon Battista Alberti.
Before Alberti the facade of Santa Maria Novella was bare like many other Florentine churches including Santa Maria del Fiore, Santa Croce and San Lorenzo. To make matters worse, six “tombs encased in marble”, i.e. six graves of noble citizens, were embedded in the facade and immovable since they were situated under as many arches and two smaller rather unattractive doors, decorated in the style of the period and covered with white and dark green striped marble.
Alberti’s greatness proved the glue necessary for a "modern" solution using a rigid Gothic structure, i.e. the ability to harmonize nobly the existing elements with the new style.
The facade reflects the influences of then recently rediscovered geometric and mathematical studies applied to nature and art that were a part of the revival of Platonic philosophy which found its center in the Florence of the day. Triangles, circles, squares, rectangles and attached geometrical figures cover the architectural landscaped designed by the brilliant architect to form a wonderful series of harmonic relationships.
First of all, he delineated the boundary of the rectangular base with two large pillars, between which he placed four columns, supporting a cornice decorated with a first motif, the Rucellai family emblem. Between the two central columns he opened a large arched portal, hemmed in by two pillars with Corinthian capitals. The three lunettes above the doors were painted by Ulisse Cocchi.
The left side of the facade features the bronze equinoctial armillary (1572) while the right side boasts a marble astronomical dial (1574), both the works of the Dominican Ignazio Danti, and astronomer and cartographer of the Grand Duchy of Tuscany.
The first pediment supports a broad band of decorated squares, over which extends a second cornice. Here starts the upper wall of the nave, attached to the cornices by four half pillars with the pre-existing large circular window in the middle and the two "ears" decorated with rosettes of inlaid marble on either side.
Finally, the wall is crowned above by a triangle, the Tympanum, with a large sun in the center, emblem of the neighborhood and the convent of Santa Maria Novella.