Comparing Old St. Peter’s Basilica and the Duomo di Pisa

Lillian Smith

November, 2021

Comparing Old St. Peter’s Basilica and the Duomo di Pisa

Situated in the Vatican City State in Rome, Italy, is St. Peter’s Basilica: one of the world’s major basilicas. The original structure, referred to as Old St. Peter’s, was commissioned by Emperor Constantine (r. 306-337) around c. 325, and was completed about 30 years later (Stokstad and Cothren:226). This ancient Roman basilica stood for nearly 1,200 years before being demolished and replaced in the 16th century during the High Renaissance. The architecture of Old St. Peter’s has helped to characterize Christian basilican churches ever since, including that of the Duomo di Pisa in Pisa, a city in Tuscany, Italy. This church, also known as the Pisa Cathedral, began construction in c. 1063, and was designed by Italian architect Buscheto (“Pisa Cathedral.”). Whether from a religious, cultural, or artistical aspect, Old St. Peter’s—as well as its reconstruction— and the Duomo are historically fascinating structures that became grand, influential pieces of architecture.

Fundamentally, basilicas were government buildings in ancient Rome that were built for public usage and were a center for public power (Mauro). They were large, hall-like structures with facilities for business and trading, markets, and covered promenades (“Basilica.” [Encyclopædia]). Courts were also held at these communal buildings. Usually, there was a center aisle and side aisles, each separated by large, evenly spaced columns that supported the roof. Basilicas were also known for having a rounded end of the building with an altar and a raised platform on which magistrates would sit, or a statue of an emperor might be placed.

In early Christianity, similar architectural features were incorporated into some Christian churches when adopting the basilica title (“Basilica.” [Wikipedia]). Those elements were also given names; for instance, the center aisle became known as a nave, and the semicircular projection on one end of the structure, an apse. Churches also became basilicas when designated by a pope because of historical significance or a place of worship associated with a major saint.

Old St. Peter’s certainly has such an association with a saint, as well as an important religious history. Construction began during the early 4th century when Emperor Constantine—the first Roman emperor to convert to Christianity— had several major basilicas built for Christian liturgical and the growing number of believers. At that date, worshippers could express their faith freely, but for more than 200 years prior, many Christians faced persecution for their religious beliefs (“Persecution of Christians.”). This martyrdom began under the rule of Roman Emperor Nero (r. 54-68) and ended when Constantine defeated Maxentius (r. 306-312) at the Battle of Milvian Bridge. At the time of his victory, Constantine issued the Edict of Milan which legalized Christianity—and tolerance for all religions— in the Roman Empire.

Near the beginning of this oppression, one man who was crucified under the command of Emperor Nero was Peter, an Apostle of Christ, and the saint for whom Old St. Peter’s was named after. It is believed that Peter was buried in the Roman cemetery on Vatican Hill, the very slope where the basilica was built (“St. Peter's Basilica Consecrated.”). Despite the ground being somewhat unlevel and making for a more challenging build, this may indicate that Constantine purposefully wanted to have the basilica erected there to mark Peter’s grave.

The construction of the Duomo was also built following a victorious battle. During the latter half of the 10th century, Pisa began rising to maritime power. The city ended up becoming one of Italy’s four main maritime republics with a remarkable merchant navy and fleet by the 11th century (“Pisa”). They also had control over many Mediterranean islands and overseas lands. In c. 1063, the Pisan fleet were triumphant in a battle against the Saracen pirates—Sicilians— in Palermo, with whom they had been in constant conflict. The gold that was confiscated from the Saracens helped to fund the construction for a new church dedicated to the Virgin Mary, the Pisa Cathedral, as well as other monuments in the same complex. There is a marble plaque outside of the cathedral’s main door with an inscription that memorializes this event.

Both Old St. Peter’s was quite a sizable structure, as is the Duomo. The original architecture of Old St. Peter’s is believed to have been about 350’ in length and could house up to 14,000 people. In fact, it was “the largest church in Christendom until the 11th century” (Stokstad & Cothren:226). The architecture of the Duomo was built with Romanesque elements, or more distinctly, Pisan Romanesque: a local variant that was developed in Pisa (“Romanesque Art.”). This style was influenced by ancient Roman, Islamic, and Byzantine architecture. It resulted during the High Middle Ages due to significant growth of Monasticism—monkhood— and larger churches were needed to make room for the rising number of religious practitioners. The Duomo was built wider and more compact than structures built in the European Romanesque style. This cathedral is about 328’ long and 177’ wide (“Cathedral of Pisa”).  

Elements of the early Christian basilica were incorporated into both Old St. Peter’s and the Pisa Cathedral. Reconstruction drawings and other basilicas of the time give us a better idea what the former must have looked like, as there were few remaining traces of the original structure (Stokstad and Cothren:226). It is believed to have had five aisles with the nave leading to an apse. There were nave colonnades which supported the entablature, smaller columns on the side aisles supporting the arches, and the roofs were braced by wooden rafters. The building was two stories tall and had clerestory windows. A large atrium was eventually added on opposite of the apse later in the 4th century. It is also believed that Old St. Peter’s had a baptistry—as many were getting baptized at the time— based on a few different sources and their inscriptions (Mckitterick:81).    

The nave in Old St. Peter’s also led to a transept (in front of the apse) which gave the building the shape of a Latin cross (“Old St. Peter's Basilica.”). This structural design is what allowed for the space to hold such a large quantity of people. The crossing—where the transept intersects with the nave—would’ve concentrated attention on Saint Peter’s tomb (“The Romanization of Christianity.”). While transepts did become fairly universal, they were infrequently used at the time; Old St. Peter’s is only one of a few examples from that period of basilicas that had these “arms”. It wasn’t until centuries later that they became more of a standard component in Christian churches. This includes the Duomo, although it was originally built in another shape.

Over the duration of the Pisa Cathedral’s construction, there were two main architects who worked on the site. In the mid-11th century, Buscheto designed and constructed the body of the Duomo, and did so in the shape of a Greek cross (“Pisa Cathedral”). With this layout, all of the “arms” are of equal length. In the early 12th century, around the time of Buscheto’s death, he was succeeded by Rainaldo. Rainaldo expanded the cathedral by lengthening one of the “arms” to take on the shape of the Latin cross. The interior of the Duomo has a central nave with two rows of granite columns, and two aisles on each side separated by smaller colonnades. There are three apses: an eastern apse, and northern and southern apses on the ends of the three-naved transept.

One of the Pisan Romanesque features inside the Duomo is a raised matronea, which is a gallery in the nave on top of the colonnades, originally for the accommodation of women. However, it was eventually only used for the “structural purpose of containing the thrust of the central nave, and came to consist solely of bays so placed” (“Triforium”). This style can also be seen in the building material, which differs from that of the brick and concrete often used in ancient Roman architecture. “The exteriors of Tuscan churches were richly decorated with marble… At Pisa, pilasters, applied arcades, and narrow galleries in white marble adorn the five-story façade” (Stokstad and Cothren:483).

The Duomo’s monumental façade is considered to be one of Rainaldo’s masterpieces. The vertical lines of white and black marbling are a masonry technique called ablaq, an interchanging of light and dark shades of stones (“Ablaq.”). This can also be seen in the columns and lancet arch windows on the interior of the Duomo. It’s a feature of Islamic architecture derived from the ancient Byzantine Empire. There are multicolored touches of marble decorating the 111’ tall façade as well (“Pisa Cathedral”). Also adorning the wall of Rainaldo’s frontispiece are blind arches, which are ornamental columns supporting arches without openings. Horizontal lines are formed by the levels of columns and arcades. Above the three doorways at the bottom of the façade are four levels of loggia, “divided by cornices with marble intarsia, behind which open single, double, and triple windows” (Ibid). The incorporation of Rainaldo’s façade was visually very cohesively and beautifully fused with the cathedral’s body.

As remarkable as Old St. Peter’s and the Duomo are, the reconstruction of the former is also quite impressive. Many centuries after Old St. Peter’s completion, it fell into ruin due to neglect. There had been an attempt at renovation during the mid-15th century, but architect Leon Battista Alberti (b. 1404-d. 1472) believed that it wouldn’t take much for it to collapse (“Old St. Peter's Basilica.”). It was in the early 16th century that Pope Julius II decided to have the old structure rebuilt. He commissioned a competition for a grand design of the new basilica, and it was won by Donato Bramante (b. 1444-d. 1514), the first High Renaissance architect. The construction for St. Peter’s Basilica began in c. 1506 and continued for about 120 years (“St Peters Basilica.” [Designing Buildings]). Shortly into the project however, Bramante died. He only lived long enough to see the four main piers that were built to support a dome he had planned for the top of the basilica.

It was then that many other Italian artists and architects succeeded Bramante; the most notable being Raphael (b. 1483-d. 1520), Gian Lorenzo Bernini (b. 1598-d. 1680), and Michelangelo (b. 1475-d. 1564) (“St Peters Basilica.” [Designing Buildings]). These men are considered to be masters of the Renaissance. Each made alterations to the Bramante’s original plan, but Michelangelo was largely attributed to the design of the travertine stone structure and its renowned dome. He designed the new structure “without destroying the centralising features of Bramante's plan… with few strokes of the pen converted its snowflake complexity into massive, cohesive unity” (“St. Peter's Basilica.” [Wikipedia]).

A couple hundred years before the reconstruction of Old St. Peter’s, a grand dome had been built on a groin vault at the Pisa Cathedral’s crossing in the early 1300s. It was one of the earliest Romanesque domes to have been constructed, as well as one of the largest; this marble dome is about 157’ tall (“History.”). One of the reasons for its elliptical shape, which sets it apart from the more typical spherical domes of the period, may be because the dome wasn’t initially envisioned in the plan for the cathedral. This untraditional shape accommodated its rectangular crossing bay.

The dome at St. Peter’s, however, is spherical. Michelangelo found a stable way to secure the dome by building four pendentives, which are a “triangular segment of a spherical surface, filling in the upper corners of a room, in order to form, at the top, a circular support for a dome” (“Pendentive.”). Once the dome was completed, it became known as the largest in the world; the total height from the floor to the cross on the top of the dome is around 488’ tall (“St Peters Basilica.” [Designing Buildings]). The cohesive unity and precision that Michelangelo used to create this exemplary dome are characteristics of the High Renaissance. Another element of this style was incorporated in front of St. Peter’s years after its completion; Doric colonnades surrounded St. Peter’s Square, the plaza in which Bernini designed and built in the mid-1600s.

Right before the 17th century, an unfortunate fire burned down the Duomo, and only a few things survived. One of which is the door of Saint Reinerius, depicting twenty-four stories of the New Testament with bronze relief decorations (“Pisa Cathedral”). This door was in the transept of the same name, and was cast by Italian sculptor Bonanno Pisano around c. 1180. Several commissions from the early 12th century that didn’t succumb to the flames are Cimabue’s (b.1240-d. 1302) apse mosaic, Christ enthroned with the Virgin and St John, and Giovanni Pisano’s (b.1250-d. 1315) pulpit. The latter is considered to be a Gothic masterpiece; there are sculpted figures around the polygonal structure and on the slightly curved panels, as well as on the column’s capitals (“Giovanni Pisano”). The figures are from both testaments of the Bible, reflecting narratives of Christ’s life. Nicola Pisano (b. 1220-d. 1284), Giovanni’s father, is credited with the synthesis of the French Gothic style with the Classical style of ancient Rome. Nicola even designed a pulpit for the Pisa Baptistry, which is in the same piazza as the Duomo, and is considered to be quite a sculptural work of art in itself.

Though nothing really remains of the many original sculptures, mosaics, and artifacts from Old St. Peter’s, its reconstruction ended up becoming a great architectural Renaissance masterpiece.

Not only that, but the interior of St. Peter’s has some beautiful pieces and is highly ornamented with reliefs, marble, and gilding (“St. Peter's Basilica.” [Wikipedia]). In the center of the basilica is the Papal Altar (c. 1623-1634) and a sculpted, bronze baldachin in the Baroque style above it, which is the work of Bernini. Below the ground, under this canopy, is where Saint Peter’s tomb lies. St. Peter’s also houses another Bernini work, the Chair of Saint Peter (c. 1666)—represented in the apse— as well as Michelangelo’s Pieta sculpture (c. 1500).

While much more could be said about both the old and new St. Peter’s, one of the most significant aspects about this sacred place is that it has been referred to as the “bedrock” of Christian faith. This metaphor is fascinating because of its association with certain verses in the Holy Bible. Peter’s name was originally Simon, changed by Jesus because of the important role that He gave to Simon in the early (universal) church. In Matthew 16:15-18, Jesus said to his apostle:

“’…Who do you say I am?’ Simon Peter answered, ‘You are the Messiah, the Son of the living God.’ Jesus replied, ‘Blessed are you, Simon son of Jonah, for this was not revealed to you by flesh and blood, but by my Father in Heaven. And I tell you that you are Peter, and on this rock I will build my church…’”

The name Peter was derived from the Greek word Petros, meaning ‘rock’ (“Saint Peter”). He was given another name with the same meaning: the Aramaic name Cephas (‘rock’ or ‘stone’). Both figuratively and literally, Peter became a part of the foundation—the bedrock— for Jesus’s truth.

These architectural masterpieces are significant with how they display different period styles in Italy, as well as their influences and the developments that were made. They are also remarkable examples of creation, complexity, and innovation executed by master artisans. These awe-inspiring structures are reminders of what has preceded us culturally, and represent the importance, endurance, and freedom of religion.

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