The nucleus of this building with the remarkable façade at Piazza Bellini is from the early 1500s, although no sources from that period still exist that might let us know the precise date or the name of the architect. The building was redone in the mid-1600s, and that, too, is sketchy, although the best educated guess from people who know about such things is that what one sees today is largely the result of the busiest and greatest of all Neapolitan architects from the 1600s, Cosimo Fanzago (1593-1678). At work, too, was Jacopo Lazzari, who also worked on the famous Capella Sansevero.

The name Firrao is of Norman origin; the earliest bearers of this name in Italian history were followers of Robert Guiscard, the great Norman conqueror whose exploits in the eleventh century paved the way for the foundation of the Kingdom of Sicily (later, Kingdom of Naples). In 1600, when Naples was a Spanish vice-realm, Cesare Firrao decided on the unique makeover of the façade to show his devotion to the Spanish throne.

The façade is virtually an encyclopedia of heraldic symbolism. I tried to understand the terminology, but I have a low threshold of patience when it comes to mantlings, swaggers, blazons, pendants and rampant horsies. I am crestfallen at my ignorance. In any event, it is all the collective effort of a number of sculptors who worked on the building. The most obvious element, of course, is the row of busts of Spanish kings. The busts are not in chronological order; they are, from left to right, Phillip IV (1605-1655), Phillip II (1527-1598), Ferdinand II (1467-1496), Charles V (1500-1588), Ferdinand III (1452-1616), Phillip III (1578-1621), and Charles II (1661-1700). Maybe Phillip IV is first because he was the monarch at the time of the reconstruction of the building. The last one is in order: Charles II, the “Little King,” the last Spanish Hapsburg, whose death without an heir ended the empire and set off the Wars of the Spanish Succession.

The building was almost destroyed during Masaniello’s Revolt in 1647 but was saved by archbishop Ascanio Filomarino, who apparently faced down the rebels in the streets and pointed to the bust of Charles V, the Holy Roman emperor and founder of the Spanish empire, a famously just person even—especially—in the eyes of the mob clamoring for what essentially was simple relief from taxation. Filomarino gave them a "Let us work together in the spirit of Charles V" pep-talk. It worked. The property has changed hands various times over the years. It currently houses the administrative offices of the Naples aqueduct.