"Agrippa finished the construction of the building called the Pantheon. It has this name, perhaps because it received among the images which decorated it the statues of many gods, including Mars and Venus; but my own opinion of the name is that, because of its vaulted roof, it resembles the heavens."
- Cassius Dio (Roman historian writing in the 3rd century AD)
What was the Pantheon used for?
Our first clue to understanding the purpose of the Pantheon comes from the word Pantheon itself.
The ancient Roman aristocracy was practically bilingual in Latin and Greek, and it was from the latter they derived the name of this temple. The Greek word for “all” was pan and the Greek for “gods” was theos.
Hence the name and purpose of the Pantheon: as a temple built in honor of all the Roman gods.
Building the Pantheon
The original Pantheon was built around 25 BC in the wake of the first emperor Augustus’ victory over his famous rivals Mark Antony and Cleopatra at the Battle of Actium in 31 BC.
Not satisfied merely with winning, Augustus wanted to advertise his victory. So he financed an elaborate building project throughout the city, celebrating, paradoxically, both the peace he’d brought and the war he’d fought to secure it.
Entrusted with carrying out this building project was Marcus Agrippa, the emperor’s right-hand man, contemporary, and son-in-law through his marriage to Augustus’ daughter Julia.
The Pantheon of Marcus Agrippa
We don’t know much about what Agrippa’s Pantheon looked like. What we do know is that he hired some of the ancient world’s finest artists, like Diogenes of Athens, to decorate it. And inside stood a statue of Venus whose earrings were made from Cleopatra’s pearls.
Agrippa built several other structures in the Campus Martius, including some public baths (the Baths of Agrippa) and the Basilica of Neptune, which housed artefacts from Augustus’ naval victory at Actium. In fact, look behind the Pantheon today and you can still see the remains of this Basilica of Neptune.
We know this much not just from ancient writers but also from the inscription on the Pantheon’s front. It reads:
M.AGRIPPA.L.F.COS.TERTIUM. FECIT
(Marcus Agrippa, the son of Lucius, built this during his third consulship.)
But the inscription is misleading. Agrippa’s Pantheon was destroyed in 80 AD in one of Rome’s many great fires. The emperor Domitian (whose father Vespasian built the
Colosseum) had it rebuilt, just as he did many other ancient monuments you see in the Roman Forum and historic center today.
Then, in 110 AD, a little over 100 years after the completion of Agrippa’s original Pantheon, the Pantheon burned down again. Everything was reduced to cinders. Everything, that is, apart from Agrippa’s original inscription.
Hadrian rebuilds the Pantheon
It was left to the incumbent emperor Hadrian to rebuild the enormous structure. And Hadrian, being the modest man that he was, decided to incorporate the original inscription, which is the one you see before you today.
What’s so special about the Pantheon Dome?
We know almost nothing about Agrippa’s original Pantheon. It could have had a dome (the word “Pantheon” meaning “Dome to the Heavens”), but we can’t say for sure. We do know lots, however, about Hadrian’s Pantheon. And one of its most intriguing features is the enormous freestanding dome.
Weighing 4,535 tons of Roman concrete, the Pantheon’s dome is an architectural marvel. It’s the
, supported by eight barrel vaults. Within the structure are arches to take some of the stress of the weight, but these are skilfully hidden behind marble facing. The Pantheon’s most famous feature is the hole in the center of its domed roof. Admittedly this causes problems when it rains or even snows. But on a beautiful Italian day, standing on the original floor of a 2,000 year old structure and gazing up at the streaming sunlight from the same spot the emperor Hadrian would have held assemblies truly is magical.
What happened to the Pantheon after the sack of Rome?
For much of the Roman Empire the Pantheon functioned as a pagan temple. Then in 609 AD, the Byzantine emperor
gifted the Pantheon to Pope Boniface IV, who duly converted the pagan temple into a Christian basilica called
. Ironically, being converted into a church saved this pagan monument. Rome’s ancient and medieval population were constantly recycling building materials from ancient structures. Fearing for their souls, however, made them far less inclined to steal from churches. The Pantheon didn’t escape completely. In 663, the emperor
stripped the Pantheon of its bronze tiles, which he shipped back to Constantinople. But the Pantheon fared better than most monuments of the Roman Empire, as a tour of the