The Roman Forum (Latin: Forum Romanum, Italian: Foro Romano) is a rectangular forum (plaza) surrounded by the ruins of several important ancient government buildings at the center of the city of Rome. Citizens of the ancient city referred to this space, originally a marketplace, as the Forum Magnum, or simply the Forum. It was for centuries the center of Roman public life: the site of triumphal processions and elections; the venue for public speeches, criminal trials, and gladiatorial matches; and the nucleus of commercial affairs. Here statues and monuments commemorated the city’s great men. The teeming heart of ancient Rome, it has been called the most celebrated meeting place in the world, and in all history. Located in the small valley between the Palatine and Capitoline Hills, the Forum today is a sprawling ruin of architectural fragments and intermittent archaeological excavations attracting 4.5 million sightseers yearly. Many of the oldest and most important structures of the ancient city were located on or near the Forum. The Roman kingdom’s earliest shrines and temples were located on the southeastern edge. These included the ancient former royal residence, the Regia (8th century BC), and the Temple of Vesta (7th century BC), as well as the surrounding complex of the Vestal Virgins, all of which were rebuilt after the rise of imperial Rome. Other archaic shrines to the northwest, such as the Umbilicus Urbis and the Vulcanal (Shrine of Vulcan), developed into the Republic’s formal Comitium (assembly area). This is where the Senate—as well as Republican government itself—began. The Senate House, government offices, tribunals, temples, memorials and statues gradually cluttered the area.

Over time the archaic Comitium was replaced by the larger adjacent Forum and the focus of judicial activity moved to the new Basilica Aemilia (179 BC). Some 130 years later, Julius Caesar built the Basilica Julia, along with the new Curia Julia, refocusing both the judicial offices and the Senate itself. This new Forum, in what proved to be its final form, then served as a revitalized city square where the people of Rome could gather for commercial, political, judicial and religious pursuits in ever greater numbers. Eventually much economic and judicial business would transfer away from the Forum Romanum to the larger and more extravagant structures (Trajan’s Forum and the Basilica Ulpia) to the north. The reign of Constantine the Great saw the construction of the last major expansion of the Forum complex—the Basilica of Maxentius (312 AD). This returned the political center to the Forum until the fall of the Western Roman Empire almost two centuries later. Unlike the later imperial fora in Rome—which were self-consciously modelled on the ancient Greek plateia (πλατεῖα) public plaza or town square—the Roman Forum developed gradually, organically and piecemeal over many centuries. This, despite attempts, with some success, to impose some order there, by Sulla, Julius Caesar and Augustus and others. By the Imperial period, the large public buildings that crowded around the central square had reduced the open area to a rectangle of about 130 by 50 metres.

Its long dimension was oriented northwest to southeast and extended from the foot of the Capitoline Hill to that of the Velian Hill. The Forum’s basilicas during the Imperial period—the Basilica Aemilia on the north and the Basilica Julia on the south—defined its long sides and its final form. The Forum proper included this square, the buildings facing it and, sometimes, an additional area (the Forum Adjectum) extending southeast as far as the Arch of Titus. Originally, the site of the Forum had been marshy lake where waters from the surrounding hills drained. This was drained by the Tarquins with the Cloaca Maxima. Because of its location, sediments from both the flooding of the Tiber River and the erosion of the surrounding hills have been raising the level of the Forum floor for centuries. Excavated sequences of remains of paving show that sediment eroded from the surrounding hills was already raising the level in early Republican times.

An important function of the Forum, during both Republican and Imperial times, was to serve as the culminating venue for the celebratory military processions known as Triumphs. Victorious generals entered the city by the western Triumphal Gate (Porta Triumphalis) and circumnavigated the Palatine Hill (counterclockwise) before proceeding from the Velian Hill down the Via Sacra and into the Forum.
From here they would mount the Capitoline Rise (Clivus Capitolinus) up to the Temple of Jupiter Optimus Maximus on the summit of the Capitol. Lavish public banquets ensued back down on the Forum. In addition to the Via Sacra, the Forum was accessed by a number of storied roads and streets, including the Vicus Jugarius, Vicus Tuscus, Argiletum, and Via Nova.)

A speculative map of Rome c. 753 BC showing the swampy situation of the early Forum between the Arx and Velia.
The original, low-lying, grassy wetland of the Forum was drained in the 7th century BC with the building of the Cloaca Maxima, a large covered sewer system that emptied into the Tiber River, as more people began to settle between the two hills.

According to tradition, the Forum’s beginnings are connected with the alliance between Romulus, the first king of Rome controlling the Palatine Hill, and his rival, Titus Tatius, who occupied the Capitoline Hill. An alliance formed after combat had been halted by the prayers and cries of the Sabine women. Because the valley lay between the two settlements, it was the designated place for the two peoples to meet. Since the early Forum area included pools of stagnant water, the most easily accessible area was the northern part of the valley which was designated as the Comitium. It was here at the Vulcanal that, according to the story, the two parties laid down their weapons and formed an alliance.

The Forum was outside the walls of the original Sabine fortress, which was entered through the Porta Saturni. These walls were mostly destroyed when the two hills were joined. The original Forum functioned as an open-air market abutting on the Comitium, but eventually outgrew its day to day shopping and marketplace role. As political speeches, civil trials, and other public affairs began to take up more and more space in the Forum, additional fora throughout the city began to emerge to expand on specific needs of the growing population. Fora for cattle, pork, vegetables and wine specialised in their niche products and the associated deities around them.

Rome’s second king, Numa Pompilius (r. 715–673 BC), is said to have begun the cult of Vesta, building its house and temple as well as the Regia as the city’s first royal palace. Later Tullus Hostilius (r. 673–642 BC) enclosed the Comitium around the old Etruscan temple where the senate would meet at the site of the Sabine conflict. He is said to have converted that temple into the Curia Hostilia close to where the Senate originally met in an old Etruscan hut. In 600 BC Tarquinius Priscus had the area paved for the first time.

During the Republican period the Comitium continued to be the central location for all judicial and political life in the city. However, in order to create a larger gathering place, the Senate began expanding the open area between the Comitium and the Temple of Vesta by purchasing existing private homes and removing them for public use. Building projects of several consuls repaved and built onto both the Comitium and the adjacent central plaza that was becoming the Forum. The 5th century BC witnessed the earliest Forum temples with known dates of construction: the Temple of Saturn (497 BC) and the Temple of Castor and Pollux (484 BC). The Temple of Concord was added in the following century, possibly by the soldier and statesman Marcus Furius Camillus. A long held tradition of speaking from the elevated speakers’ Rostra—originally facing north towards the Senate House to the assembled politicians and elites—put the orator’s back to the people assembled in the Forum. A tribune known as Caius Licinius (consul in 361 BC) is said to have been the first to turn away from the elite towards the Forum, an act symbolically repeated two centuries later by Gaius Gracchus. This began the tradition of locus popularis, in which even young nobles were expected to speak to the people from the Rostra. Gracchus was thus credited with (or accused of) disturbing the mos maiorum (“custom of the fathers/ancestors”) in ancient Rome. When Censor in 318 BC, Gaius Maenius provided buildings in the Forum neighborhood with balconies, which were called after him maeniana, in order that the spectators might better view the games put on within the temporary wooden arenas set up there.

The Tribune benches were placed on the Forum Romanum as well. Firstly they stood next to the senate house, during the late roman Republic they were placed in front of the Basilica Porcia. The earliest basilicas (large, aisled halls) were introduced to the Forum in 184 BC by Marcus Portius Cato, which began the process of “monumentalizing” the site. The Basilica Fulvia was dedicated on the north side of the Forum square in 179 BC. (It was rebuilt and renamed several times, as Basilica Fulvia et Aemilia, Basilica Paulli, Basilica Aemilia). Nine years later, the Basilica Sempronia was dedicated on the south side. Many of the traditions from the Comitium, such as the popular assemblies, funerals nobles and games, were transferred to the Forum as it developed. Especially notable was the move of the comitia tributa, then the focus of popular politics, in 145 BC. Particularly important and unprecedented political events took place in 133 BC when, in the midst of riots in and around the Forum, the Tribune Tiberius Gracchus was lynched there by a group of Senators. In the 80s BC, during the dictatorship of Sulla, major work was done on the Forum including the raising of the plaza level by almost a meter and the laying of permanent marble paving stones. (Remarkably, this level of the paving was maintained more or less intact for over a millennium: at least until the sack of Rome by Robert Guiscard and his Normans in 1084, when neglect finally allowed debris to begin to accumulate unabated.)

In 78 BC, the immense Tabularium (Records Hall) was built at the Capitoline Hill end of the Forum by order of the consuls for that year, M. Aemilius Lepidus and Q. Lutatius Catulus. In 63 BC, Cicero delivered his famous speech denouncing the companions of the conspirator Catiline at the Forum (in the Temple of Concord, whose spacious hall was sometimes used as a meeting place by the Senators). After the verdict, they were led to their deaths at the Tullianum, the nearby dungeon which was the only known state prison of the ancient Romans.

Over time, the Comitium was lost to the ever-growing Curia and to Julius Caesar’s rearrangements before his assassination in 44 BC. That year, two supremely dramatic events were witnessed by the Forum, perhaps the most famous ever to transpire there: Marc Antony’s funeral oration for Caesar (immortalized in Shakespeare’s famous play) was delivered from the partially completed speaker’s platform known as the New Rostra and the public burning of Caesar’s body occurred on a site directly across from the Rostra around which the Temple to the Deified Caesar was subsequently built by his great-nephew Octavius (Augustus). Almost two years later, Marc Antony added to the notoriety of the Rostra by publicly displaying the severed head and right hand of his enemy Cicero there.

After Julius Caesar’s death, and the end of the subsequent Civil Wars, Augustus would finish his great-uncle’s work, giving the Forum its final form. This included the southeastern end of the plaza where he constructed the Temple of Divus Iulius and the Arch of Augustus there (both in 29 BC). The Forum was witness to the assassination of a Roman Emperor in 69 AD: Galba had set out from the palace to meet rebels, but was so feeble that he had to be carried in a litter. He was immediately met by a troop of his rival Otho’s cavalry near the Lacus Curtius in the Forum, where he was killed. During these early Imperial times much economic and judicial business transferred away from the Forum to larger and more extravagant structures to the north. After the building of Trajan’s Forum (110 AD), these activities transferred to the Basilica Ulpia. The white marble Arch of Septimius Severus was added the northwest end of the Forum close to the foot of the Capitoline Hill and adjacent to the old, vanishing Comitium. It was dedicated in 203 AD to commemorate the Parthian victories of Emperor Septimius Severus and his two sons, and is one of the most visible landmarks there today. The Emperor Diocletian (r. 284-305) was the last of the great builders of Rome’s city infrastructure and he did not omit the Forum from his program. By his day it had become highly cluttered with honorific memorials. He refurbished and reorganized it, building anew the Temple of Saturn, Temple of Vesta and the Curia. The last had recently burned and Diocletian’s version is the one that can still be visited today.

The reign of Constantine the Great saw the completion of the construction of the Basilica of Maxentius (312 AD), the last significant expansion of the Forum complex. This restored much of the political focus to the Forum until the fall of the Western Roman Empire almost two centuries later.