The Theater was named after Emperor Augustus’ nephew Marcus Claudius Marcellus however the building was originally commissioned by Julius Caesar who bought and cleared the land in a space to the south of the Field of Mars amongst a cluster of Temples and next to the Tiber.
Notably, neither Julius Caesar nor Marcellus were alive at the time of the Theater’s opening – Caesar had been assassinated and Marcellus had passed away from an illness and the task of completing the project had fallen on Augustus.
The naming and official opening took place 10 years after Marcellus’s death in the same year that Augustus dedicated the Ara Pacis. Marcellus was the eldest son of Gaius Claudius Marcellus Minor, a former Roman consul, and of Octavia Minor, sister of Caesar Augustus. Marcellus, the Emperor’s nephew, married Augustus’ daughter Julia in 25 BCE thereby becoming also his son-in-law. He served under Augustus in Hispania alongside the future emperor Tiberius and was elected to a magistrate's office at a very young age, an honor Marcellus celebrated by sponsoring extraordinary public games. His rapid rise to public office and close ties to the Emperor are said to have brought him into conflict with Agrippa and others.
This promising career was cut short when Marcellus died in 23 BCE at the age of 19. At that time an illness was spreading throughout Rome and first Augustus and then Marcellus would succumb. The emperor recovered but the illness proved fatal for Marcellus who passed away in Baiae.
The architecture of the theatre had a significant influence on subsequent buildings in Rome and across the empire for example the design of the façade was reproduced in iconic buildings such as the nearby Colosseum and the Amphitheater in Verona. In particular, the theater structure had a curving double colonnade decorated on the outside with three orders or styles of columns, two of these are well preserved in the lower levels. Although now missing, the keystones of the external archways of the colonnade were decorated with ornately carved masks consistent with the tradition of Greek drama that were used by actors to show expressions of smiling or frowning.
The theatre was 111 m in diameter and was the largest and arguably the most important in Ancient Rome. It is thought to have been able to accommodate more than 20,000 spectators.
For its opening, Augustus commissioned special games and festivities. As part of this he had a golden statue of his nephew wearing a golden crown brought into the Theater and seated on a traditional Roman curule chair in amongst the dignitaries that had arranged the celebrations.
The Theater’s proximity to the river meant that the route of the city’s triumphal procession needed to be adjusted. Instead of going around the building it would be redirected to take advantage of the new facilities and passed in front of the stage and in full view of the theater’s audience. It is likely that Caesar’s original design had to be adjusted to accommodate this requirement – something that was achieved by widening the gap between the stage front and the seating.
By the early 1900s, like many of the ancient Roman buildings, the theater had become crowded with piles of old ruins, shops, shacks and slum housing. Archaeologists had undertaken some exploratory digs at the beginning of the century but, given all of the overlaid structures, it was difficult to ascertain what remained of the original theater. Mussolini ordered the area completely cleared to allow the building to be renovated and restored to a recognizable state. Clearing the site and widening adjacent roads displaced most of the occupants of the Theater to other parts of the city. By the end of the excavations in 1932, over three quarters of the façade had been revealed, the barrel-vault had been cleared, and iron gates installed.
Today the building is used as a combination of private apartments and offices however there is good access to view the remains of the outer colonnades.