I have mentioned Borromini a number of times in my posts about visits to Rome, but I have not written much about him.

He was born in 1599 by the name Francesco Castelli but changed his name to Borromini, a name in his mother’s family and some think also out of regard for Carlo Borromeo, a leading figure in the Counter-Reformation and later made a saint.

He started as a stone mason (his father was also a stone mason) but after studying in Milan, he moved to Rome in 1619 to work for the architect Carlo Maderno, a distant relative. At that time, Maderno was working on the façade of St. Peter’s Basilica as well as Palazzo Barberini. Also working on Palazzo Barberini was Gianlorenzo Bernini.

Borromini and Bernini became fierce rivals. Both worked in the Baroque style but their buildings and lives were starkly different.

Bernini was outgoing, charming and popular. He won numerous commissions from the wealthy and powerful in Rome as a sculptor, architect and painter. As he grew wealthier, he lived the life of a courtier, gentleman. Although married, he had numerous affairs. He had many disciples working under his supervision.

Borromini, on the other hand, people found difficult to deal with as he was irascible, morose and sometimes given to fits of rage. He argued with patrons and resented his lack of recognition. He was celibate, indifferent to wealth and unfashionable in his dress. He only cared about architecture and only had one assistant.

Bernini would use Borromini when it suited him. Some historians suggest Bernini exploited Borromini and took credit for some of Borromini’s work. As Bernini’s fortune and fame rose, Borromini’s declined. He committed suicide in 1667.

The two buildings that best represent Borromini’s style are the churches San Carlo alle Quattro Fontane, built between 1634-48, and Sant’Ivo alla Sapienza, built between 1642-60.

San Carlo alle Quattro Fontane, also called San Carlino, was Borromini’s first independent commission, and it showcases both his innovation and his ability to adapt to challenges. The building sits in a small space on a corner lot, surrounded by other buildings belonging to the church. Because of these adjacent buildings, Borromini had to develop a rather inventive approach to make the best use of the limited available space. Borromini’s plan took an unusual shape, somewhere between a rectangle, a cross, and an oval. Not only does this plan take advantage of the small lot on which the Church sits—it also manages to be cruciform, central-plan, and basilican all at once.

The interior is both traditional and innovative. Its walls, for example, are adorned with classical columns, but they curve around in a way that suggests movement, an effect that was fairly progressive in its time. Likewise, the façade includes elements of classical architecture and applies them in a new and innovative way. Much like Carlo Maderno’s facades, San Carlo alle Quattro Fontane is designed with two stories, each divided into bays. However, Borromini’s is further enlivened with the use of alternating convex and concave curves that result in a rippling, wavelike façade. This unusual treatment of space and the wall surface defines Borromini architecture and sets it apart from the classicizing architecture of Bernini.

Borromini is most famous for his design of Sant’Ivo, which served as the chapel for a Roman university. The church was to be built at the short end of a rectangular courtyard, meaning that, once again, Borromini was presented with the challenge of creating a building on a small plot of land.

Borromini’s church is also remarkable for the way in which it is incorporated into the surrounding architectural environment through its façade, which replicates much of the ornamentation from the flanking arcades. The arcades of the courtyard are on two stories with a dividing entablature. Each story consists of a procession of rounded arches with a pilaster between the arches. This rhythm is continued into the façade of Sant’Ivo: instead of an open arcade, there is a series of windows with “blind arches” (arches that don’t open onto anything, but are instead a part of a wall surface) and pilasters in between. Similarly, the two stories are divided by an entablature that runs directly from the entablature in the arcades of the colonnade. In true Borromini style, the entire façade is concave, adding interest and movement to an otherwise straightforward façade. The concave façade is made livelier because of the contrasting convex portion of the building hovering above.

Borromini’s unusual approach can also be seen in the interior of the building. The central-plan church takes the shape of two intersecting triangles that create a “star of David” pattern. Once again, the effect is dynamic: the walls of the star-shaped space “undulate,” so to speak, in a rhythm of alternating convex and concave curves, much like in San Carlo alle Quattro Fontane. Soaring up above the central space is a towering conical dome. The seeming movement of the interior space generates a sense of energy that culminates in the oculus at the peak of the building.

The exterior of the dome is also rather unusual for its time, with the exterior of the dome making up the majority of the upper portion of the church. At the top of the dome, there is a lantern adorned with a spiral, continuing the upward thrust of the rest of the building.

“Sapienza” means “knowledge” or “wisdom” in Italian, an appropriate dedication for a church associated with an institution of higher learning; many have speculated that the upward momentum of the church links together wisdom and spiritual faith. Whatever Borromini’s intention, the church is today considered Borromini’s masterpiece.