Pantheon, Rome

The Pantheon is an ancient 2nd century Roman temple and, since AD 609, a Catholic church called the Basilica of St. Mary and the Martyrs in Rome, Italy. It is perhaps the most famous, and architecturally most influential, rotunda.
The Pantheon was built on the site of an earlier temple, which had been commissioned by Marcus Vipsanius Agrippa during the reign of Augustus. After the original burnt down, the present building was ordered by the emperor Hadrian and probably dedicated AD 126. Its date of construction is uncertain, because Hadrian chose to re-inscribe the new temple with Agrippa's original date inscription from the older temple.
The building is round in plan, except for the portico with large granite Corinthian columns under a pediment. A rectangular vestibule links the porch to the rotunda, which is under a coffered concrete dome, with a central opening to the sky. Almost two thousand years after it was built, the Pantheon's dome is still the world's largest unreinforced concrete dome. The height to the oculus and the diameter of the interior circle are the same,.
It is one of the best-preserved of all Ancient Roman buildings, in large part because it has been in continuous use throughout its history. Since the 7th century, it has been a church dedicated to St. Mary and the Martyrs, known as "Santa Maria Rotonda". The square in front of the Pantheon is called Piazza della Rotonda. The Pantheon is a state property, managed by Italy's Ministry of Cultural Heritage and Activities and Tourism through the Polo Museale del Lazio. In 2013, it was visited by over six million people.
The Pantheon's large circular domed cella, with a conventional temple portico front, was unique in Roman architecture. Nevertheless, it became a standard exemplar when classical styles were revived, and has been copied many times by later architects.

Etymology

The name "Pantheon" is from the Ancient Greek "Pantheion" meaning "of, relating to, or common to all the gods":. The simplest explanation for the name is that the Pantheon was a temple dedicated to all the gods. However, the concept of a temple dedicated to all the gods has been questioned. Ziegler tried to collect evidence of pantheons, but his list consists of simple dedications "to all the gods" or "to the Twelve Gods", which are not necessarily true pantheons in the sense of a temple housing a cult that literally worships all the gods. The only definite pantheon recorded earlier than Agrippa's was at Antioch in Syria, though it is only mentioned by a sixth-century source. Cassius Dio, a Roman senator who wrote in Greek, speculated that the name of the Pantheon comes either from the statues of many gods placed around this building, or from the resemblance of the dome to the heavens. According to Adam Ziolkowski, this uncertainty strongly suggests that "Pantheon" was merely a nickname, not the formal name of the building.
Godfrey and Hemsoll point out that ancient authors never refer to Hadrian's Pantheon with the word aedes, as they do with other temples, and the Severan inscription carved on the architrave uses simply "Pantheum", not "Aedes Panthei". Livy wrote that it had been decreed that temple buildings should only be dedicated to single divinities, so that it would be clear who would be offended if, for example, the building was struck by lightning, and because it was only appropriate to offer sacrifice to a specific deity. Godfrey and Hemsoll maintain that the word Pantheon "need not denote a particular group of gods, or, indeed, even all the gods, since it could well have had other meanings. ... Certainly the word pantheus or pantheos, could be applicable to individual deities. ... Bearing in mind also that the Greek word θεῖος need not mean 'of a god' but could mean 'superhuman', or even 'excellent'."
Since the French Revolution, when the church of Sainte-Geneviève in Paris was deconsecrated and turned into the secular monument called the Panthéon of Paris, the generic term pantheon has sometimes been applied to other buildings in which illustrious dead are honoured or buried.

History

Ancient

In the aftermath of the Battle of Actium, Marcus Vipsanius Agrippa started an impressive building program. The Pantheon was a part of the complex created by him on his own property in the Campus Martius in 29–19 BC, which included three buildings aligned from south to north: the Baths of Agrippa, the Basilica of Neptune, and the Pantheon. It seems likely that the Pantheon and the Basilica of Neptune were Agrippa's sacra privata, not aedes publicae. The former would help explain how the building could have so easily lost its original name and purpose in such a relatively short period of time.
It had long been thought that the current building was built by Agrippa, with later alterations undertaken, and this was in part because of the Latin inscription on the front of the temple which reads: However, archaeological excavations have shown that the Pantheon of Agrippa had been completely destroyed except for the façade. Lise Hetland argues that the present construction began in 114, under Trajan, four years after it was destroyed by fire for the second time. She reexamined Herbert Bloch's 1959 paper, which is responsible for the commonly maintained Hadrianic date, and maintains that he should not have excluded all of the Trajanic-era bricks from his brick-stamp study. Her argument is particularly interesting in light of Heilmeyer's argument that, based on stylistic evidence, Apollodorus of Damascus, Trajan's architect, was the obvious architect.
The form of Agrippa's Pantheon is debated. As a result of excavations in the late 19th century, archaeologist Rodolfo Lanciani concluded that Agrippa's Pantheon was oriented so that it faced south, in contrast with the current layout that faces north, and that it had a shortened T-shaped plan with the entrance at the base of the "T". This description was widely accepted until the late 20th century. While more recent archaeological diggings have suggested that Agrippa's building might have had a circular form with a triangular porch, and it might have also faced north, much like the later rebuildings, Ziolkowski complains that their conclusions were based entirely on surmise; according to him, they did not find any new datable material, yet they attributed everything they found to the Agrippan phase, failing to account for the fact that Domitian, known for his enthusiasm for building and known to have restored the Pantheon after 80 AD, might well have been responsible for everything they found. Ziolkowski argues that Lanciani's initial assessment is still supported by all of the finds to date, including theirs; he expresses scepticism because the building they describe, "a single building composed of a huge pronaos and a circular cella of the same diameter, linked by a relatively narrow and very short passage, has no known parallels in classical architecture and would go against everything we know of Roman design principles in general and of Augustan architecture in particular."
The only passages referring to the decoration of the Agrippan Pantheon written by an eyewitness are in Pliny the Elder's Natural History. From him we know that "the capitals, too, of the pillars, which were placed by M. Agrippa in the Pantheon, are made of Syracusan bronze", that "the Pantheon of Agrippa has been decorated by Diogenes of Athens, and the Caryatides, by him, which form the columns of that temple, are looked upon as masterpieces of excellence: the same, too, with the statues that are placed upon the roof," and that one of Cleopatra's pearls was cut in half so that each half "might serve as pendants for the ears of Venus, in the Pantheon at Rome".
The Augustan Pantheon was destroyed along with other buildings in a fire in 80 AD. Domitian rebuilt the Pantheon, which was burnt again in 110 AD.
The degree to which the decorative scheme should be credited to Hadrian's architects is uncertain. Finished by Hadrian but not claimed as one of his works, it used the text of the original inscription on the new façade. How the building was actually used is not known. The Historia Augusta says that Hadrian dedicated the Pantheon in the name of the original builder, but the current inscription could not be a copy of the original; it does not tell us to whom Agrippa's foundation was dedicated, and, in Ziolkowski's opinion, it was highly unlikely that in 25 BC Agrippa would have presented himself as "consul tertium." On coins, the same words, "M. Agrippa L.f cos. tertium", were the ones used to refer to him after his death; consul tertium serving as "a sort of posthumous cognomen ex virtute, a remembrance of the fact that, of all the men of his generation apart from Augustus himself, he was the only one to hold the consulship thrice." Whatever the cause of the alteration of the inscription might have been, the new inscription reflects the fact that there was a change in the building's purpose.
Cassius Dio, a Graeco-Roman senator, consul and author of a comprehensive History of Rome, writing approximately 75 years after the Pantheon's reconstruction, mistakenly attributed the domed building to Agrippa rather than Hadrian. Dio appears to be the only near-contemporaneous writer to mention the Pantheon. Even by 200, there was uncertainty about the origin of the building and its purpose:
In 202, the building was repaired by the joint emperors Septimius Severus and his son Caracalla, for which there is another, smaller inscription on the architrave of the façade, under the aforementioned larger text. This now-barely legible inscription reads:
In English, this means:

Medieval

In 609, the Byzantine emperor Phocas gave the building to Pope Boniface IV, who converted it into a Christian church and consecrated it to St. Mary and the Martyrs on 13 May 609: "Another Pope, Boniface, asked the same to order that in the old temple called the Pantheon, after the pagan filth was removed, a church should be made, to the holy virgin Mary and all the martyrs, so that the commemoration of the saints would take place henceforth where not gods but demons were formerly worshipped." Twenty-eight cartloads of holy relics of martyrs were said to have been removed from the catacombs and placed in a porphyry basin beneath the high altar. On its consecration, Boniface placed an icon of the Mother of God as 'Panagia Hodegetria' within the new sanctuary.
The building's consecration as a church saved it from the abandonment, destruction, and the worst of the spoliation that befell the majority of ancient Rome's buildings during the Early Middle Ages. However, Paul the Deacon records the spoliation of the building by the Emperor Constans II, who visited Rome in July 663:

Remaining at Rome twelve days he pulled down everything that in ancient times had been made of metal for the ornament of the city, to such an extent that he even stripped off the roof of the church , which at one time was called the Pantheon, and had been founded in honour of all the gods and was now by the consent of the former rulers the place of all the martyrs; and he took away from there the bronze tiles and sent them with all the other ornaments to Constantinople.

Much fine external marble has been removed over the centuries – for example, capitals from some of the pilasters are in the British Museum. Two columns were swallowed up in the medieval buildings that abutted the Pantheon on the east and were lost. In the early 17th century, Urban VIII Barberini tore away the bronze ceiling of the portico, and replaced the medieval campanile with the famous twin towers called "the ass's ears", which were not removed until the late 19th century. The only other loss has been the external sculptures, which adorned the pediment above Agrippa's inscription. The marble interior has largely survived, although with extensive restoration.