The forum was designed to be the center of Roman political and economic life, and included several important buildings such as the Temple of Venus Genetrix and the Curia Julia (the meeting place of the Roman Senate). It also served as a location for important political and religious events and was decorated with statues and other works of art. The forum was a major center of Roman life for several centuries, but fell into disuse and ruin after the fall of the Western Roman Empire in the fifth century CE.

circa 46 BCE

Late Republican Period
The Forum of Julius Caesar (Latin Forum Iulium), also known as the Forum Julium or Forum Caesaris, was initiated by Gaius Julius Caesar during his rise to undisputed political dominance in the final decades of the Roman Republic. The project was formally undertaken around 54 BCE, amid Caesar’s consolidation of power following his proconsulship in Gaul and in the context of increasing political instability in Rome.

The forum was conceived as an extension to the already congested Roman Forum, with the dual function of easing legal and commercial overflow while simultaneously serving as a visual assertion of Caesar’s authority. Its dedication to Venus Genetrix, the divine progenitor of the Julian line according to Caesar’s own propaganda, further embedded his family within Rome’s mytho-political narrative. Construction of the forum was financed, in part, from spoils of the Gallic Wars, and its planning coincided with Caesar’s gradual transformation from princeps senatus to de facto autocrat.

Although the Julian Forum was inaugurated in 46 BCE during Caesar’s lifetime, it remained incomplete at the time of his assassination in 44 BCE. The hasty dedication suggests its use as a tool for immediate political legitimation in the turbulent post–civil war period. The central Temple of Venus Genetrix was the focal point of the complex, serving both as a cultic space and as a symbolic statement of Caesar’s divine affiliation. The choice of Venus as patron was also a deliberate counterpoint to Mars, the patron of later Fori Imperiali (imperial fora), indicating a distinct rhetorical register in Caesar’s self-representation as a civil rather than merely martial restorer of Rome.

Julio-Claudian Period
After Caesar’s assassination, the Forum Iulium gained further political weight under the control of the Second Triumvirate and then Augustus. Octavian, Caesar’s adoptive son and heir, completed the forum’s construction and enhanced its symbolic association with the Julian lineage. The forum became a regular venue for judicial proceedings and senatorial activity, reinforcing the continuity between the Republic and the emerging principate.

Augustus did not significantly alter the forum’s original layout but reinforced its ideological program through additional statues, inscriptions, and careful curatorial control. The temple housed cult images of Caesar and Venus Genetrix, including one of Caesar himself placed posthumously among the ranks of the divinized. The forum's use in public rituals and political ceremonies under Augustus made it a critical site for the performative articulation of dynastic legitimacy.

Early Imperial Period
During the early first century CE, the Forum of Julius Caesar remained in active administrative and symbolic use, though its prominence gradually diminished as new monumental fora were constructed by successive emperors. It remained under maintenance and was occasionally refurbished, particularly under Tiberius and Claudius, as part of their broader program of urban continuity and pietas toward the Julian legacy.

The fire of 80 CE under Titus severely damaged the forum. It was restored by Domitian and further reworked by Trajan, though without substantive ideological revision. The architectural restoration preserved the forum’s foundational messaging but situated it within a broader continuum of imperial monumentalism that would culminate in Trajan’s own forum, adjacent to and partially integrated with the Forum Iulium.

Later Imperial Period
In the second and third centuries CE, the Forum of Julius Caesar retained symbolic and ceremonial relevance but increasingly receded from the political center of gravity. The urban focus of Rome shifted further toward newer complexes such as the Forum of emperor Trajan and the Baths of Caracalla, while the Forum Iulium became a site of memory more than of active governance.

Epigraphic and literary sources from the Severan and later periods indicate periodic repairs but no significant reinterpretation of the space. The ideological content of the forum, grounded in the Julian mythos and the Republican-to-imperial transition, remained fixed and was not substantially reappropriated by later dynasties.

Late Antiquity and Obsolescence
By the fourth century CE, the Forum of Julius Caesar, like much of the imperial fora complex, had fallen into partial disuse amid broader urban decline and the restructuring of the city’s religious and political institutions. With the Christianization of imperial ideology and the relocation of the administrative center to Constantinople, the forum’s ideological core lost its resonance. The Temple of Venus Genetrix, associated with the Roman imperial cult, likely ceased functioning by the end of the fourth century.

The site was progressively quarried for building material and eventually obscured by later medieval and Renaissance constructions. Its historical identity persisted through scattered literary references, but the physical space was not systematically recovered until excavations in the twentieth century.

Today, the Forum of Julius Caesar is recognized as a pivotal monument in Rome’s architectural and political history, marking the point of transition between the late Republic and the Augustan principate through monumentalized political narrative rather than mere spatial expansion.

circa 46 BCE

Central Square and Surrounding Porticos
The square of the Caesar's Forum was built on the architectural model of the Greek porticoes. It presents a temple at the centre of one of its short sides following the Etruscan and Italic fashion. The Forum, with a rectangular plan, was actually surrounded on three sides by porticoes with rooms (shops or offices).

circa 46 BCE

Temple of Venus Genetrix
The Temple of Venus Genetrix dominated the center of the fourth side. Close to the Temple of Venus Genetrix there was a hilly area which was dug out for the construction of the emperor Trajan's Forum (built circa 112-113 CE). This intervention also involved important works in the Forum of Caesar and the reconstruction of the Temple itself.

The Temple of Venus Genetrix was dedicated by Caesar on 26 September, 46 BCE, the last day of his triumph (Cassius Dio, XLIII.22.1-3). It was of marble (Ovid, Art of Love, I.81), almost square, Corinthian, with eight columns across the front (octastyle) set very close together (the diameter of one and one-half columns (pycnostyle); Vitruvius cites the temple as an example of the type, III.3.2) and eight down each side (peripteral). The high podium rose sheer in front and was ascended by two small lateral staircases. Inside the cella, there was a statue of Venus, as well as statues of Caesar and Cleopatra (Dio, LI.22.3; Appian, Civil Wars, II.102); numerous works of art, including Greek paintings; six collections of engraved gems (dactyliothecae); and a breastplate decorated with pearls from Britannia.

The area was damaged by the fire of 80 CE and the temple was extensively rebuilt by Domitian (as can be seen in the Flavian style of the cornice). It was rededicated by Trajan in 113 CE, the year his own forum was dedicated. The columns and entablature that were re-erected in the 1930s CE belong to that restoration. The rest of the forum lies in ruins.

The original temple built by Julius Caesar has not survived and the remains of the Temple of Venus Genetrix visible today are almost all those of emperor Domitian, who probably began work on the Forum Julium soon after the rebuilding of the Curia Julia in 94 CE. One characteristic of this work is the deeply cut egg-and-dart molding of the cornice and the tiny rings (anelli) between the dentils, which are very similar to the molding in Domitian's Forum Transitorium, all of which usually are attributed to Domitian's architect Rabirius. In this richly carved fragment from the cornice, one can see rosettes between the modillions and, below them, the egg motif and dentils.

circa 46 BCE

Southern Portico and the Piazza of Caesar's Forum
The Forum of Caesar was in fact constructed on an immense rectangular piazza measuring around 100 x 45 meters, and was covered on three sides (east, west and south) by colonnaded porticos, with two aisles and on the northern end of this plaza, stood the Temple of Venus Genetrix. The ruins of the podium and part of the western colonnade were recreated in 1933 CE.

In the pre-historic era of Rome's history (circa tenth and ninth centuries BCE) this area was originally a burial ground, where some tombs were discovered during excavations made in 1998-2000 CE. During the age of the Roman Republic, this was a rich residential area that was extensively demolished to allow space for the Caesar's Forum.

The current imposing structures of the Forum of Caesar and the Curia Julia (which is directly adjanct to the southern portico) date back to the restoration work carried out in the Forum by the emperors Maxentius and Diocletian, following the fire of 283 CE. The remains of the coloured marble flooring of the southern portico belong to the same period as well. As part of the renovation works, the central row of columns was removed in the southern portico and the space was transformed in to a huge room attached to the Curia Julia.

circa 46 BCE

Basilica Argentaria
The basilica Argentaria is situated in the north-western corner of the Caesar's Forum at the foot of the Capitoline hill. Although today the basilica Argentaria forms part of the archaeological site of Caesar's Forum, it was most likely built at some time afterwards, since it does not appears in any sources before the late Constantinian period. The building was erected under Trajan, with the purpose of adapting the slopes of the Capitoline Hill after the removal of the gap between it and the Quirinal Hill.

The basilica-argentaria was installed in the two row portico of pillars made of tuff stones and its naves were created by covering them with barrel vaults, partially preserved. The basilica was built higher than the level of the forum's square and the access was through two staircases on the south-west end of the portico. As the basilica rose in an obligated space, it has an irregular floor plan, turning round the temple and probably continuing out of the present archaeological area, close to the south-west exedra of the Trajan's Forum.

The partially preserved plaster covering the back wall of the structure, displays several graffiti, some of which quote lines of the Aeneid. This particular detail points to the possibility that the basilica may have housed a school, mentioned by late sources about the Trajan's Forum and the Forum of Augustus.