Layers of Rome: An Architectural and Historical Analysis of the Forum of Augustus

Nov 2023
10-minute read

The Layers of Rome project is currently working toward developing a virtual walking tour of the Old and Imperial fora of Rome. Our ultimate goal is to make Roman history more accessible to the general public, as it is immensely difficult to make sense of a field of ruined structures without prior reading. It is our hope that the Layers of Rome map will be able to bridge the divide between site and context with a brief summation about chosen sites accompanied by reconstructed images of the sites as they stood in antiquity. As it is intended to be used on-site while visitors stand amidst the ruins in the (at times oppressive) Italian heat, the map’s site descriptions have been limited to 300 words. What follows is an in-depth architectural and historical analysis of the Forum of Augustus that a mere 300 words could never hope to adequately describe.

The Forum of Augustus itself is a masterpiece of imperial propaganda, wrought in solid Carrara marble by Augustus’ architects. From the Via dei Fori Imperiali, all that one can discern of the once-great Forum of Augustus are the stairs, podium, and a miraculously still-standing section of cella(1) wall and columns that once comprised the Temple of Mars Ultor. Apart from these, all that remains of the rest of the forum lies shattered on the floor below. A ghost of the two-story portico(2) that once flanked either side of the temple can be seen etched into the fire wall to the right of the temple ruins. It was this now ruinous space that birthed the Augustan style and message—a space about which Pliny the Elder remarked, "Should we not mention among our truly noble buildings . . . the Forum of Augustus . . . buildings the most beautiful the world has ever seen?"(3)

(Figure 1) Temple of Mars Ultor in Forum of Augustus (image courtesy of Josh Muñoz).

The Forum of Augustus owes its inception to a vow made amidst the fury of battle by the triumvir(4), Octavian, to Mars, god of war, promising a grand temple should victory be his. The stakes at the Battle of Phillipi in 42 BC couldn’t have been higher. Alongside his fellow triumvir, Marcus Antonius, Octavian was locked in a climactic struggle for control of the empire against Brutus and Cassius—arch conspirators who had murdered his adoptive father, Julius Caesar—and who now sought to reestablish the dominance of the senate over the Roman state. Thirty-six legions—180,000 men—fought tooth-and-nail for the soul of the republic. When the dust had cleared and the sun had set over the battlefield, Brutus and Cassius lay dead along with thousands of their men. The civil war was finally over, and Caesar was avenged.

In the ensuing decade, Octavian’s power and influence grew. After defeating his treacherous partner, Marcus Antonius, and his mistress, Egyptian Pharaoh Cleopatra, at the battle of Actium, Octavian had, at last, restored peace to the Roman world, bringing decades of civil war to a close. With absolute power now functionally his, Octavian was granted the title of Augustus in 27 BC, a title that would lead history to recognize him as the first emperor of Rome.

(Figure 2) Augustus as Imperator Augustus of Primaporta Vatican Museums (image courtesy of Josh Muñoz).

It is likely that construction of the temple and its accompanying forum did not begin until after 20 BC, when Augustus had recovered the eagle standards of the legions lost under Crassus in 53 BC that he personally retrieved after a bloodless campaign against the Parthians. In thanksgiving for these great victories and attaining retribution for both his father’s murder and the dishonor of Crassus’ defeat, Augustus would have commenced with fulfilling his vow.

The Temple of Mars Ultor (Mars the Avenger) took center stage in the heart of Augustus’ new forum, where Augustus would place the recovered standards of Crassus and, later, the recovered eagle standards of the XVII, XVIII, and XIX Legions that were lost in the Varian disaster of 9 AD(5).

The forum in its design deliberately evokes the form of the Forum Iulium(6), which directly abuts the Forum of Augustus at its lower end. This was perhaps done by Augustus to establish a certain continuity, a sense of dynasty even, with the rule of his adoptive father Julius Caesar. The Forum of Augustus, like that of Caesar, consists of a vast open piazza, a statue of the Princeps(7) in his quadriga(8), the Temple of Mars Ultor at its far end, and is framed by a two-story portico terminating at the fire wall behind the forum. It evokes Caesar, and yet surpasses him. Rather than a simple rectangular design, the porticoes of the Forum of Augustus flare outward forming two grand exedrae(9) just before the colonnade reaches the point of the podium of the temple. Also, the brick-and-mortar structures of Caesar, merely veneered in stucco and thin slabs of marble, give way to the gleaming white, solid Carrara marble edifices for which Augustus will later boast.

(Figure 3) Rome: Forum of Augustus: Plan with Iconographic Scheme. 42-2 B.C.

Building temples of solid marble as votive offerings to the gods had always been a hallmark of Hellenic piety, with the Romans preferring, to the horror of the Greeks, to construct their temples of cheap, abundant materials, giving them a finish that granted merely the appearance of lavish expense. Augustus dispels with Roman economy and raises his forum to the height of splendor worthy of a son of the divine. The eight gleaming marble columns fronting the temple of Mars deliberately evoke the Parthenon of Athens, the epicenter of classical civilization and culture in the Mediterranean. The Caryatids of the Erechtheion at the acropolis themselves were employed to decorate the attics of the porticos of the forum. With these elements enshrined in his forum, Augustus was announcing that Greece had been usurped as the cultural center of the classical world, that the crown of Athena Parthenos now belonged to Roma.

(Figure 4) Reconstructive view of the Forum of Augustus during Augustan age (Museo dei Fori Imperiali Rome)

(Figure 5) Rome: Forum of Augustus: Attic Story of Portico with Flanking Colonnades of Caryatids. n.d.

The cultural message dictated by Augustus through his forum was equally matched by his political messaging. Each of the two porticoes hosted a collection of statues housed in niches along the walls, one hundred or more in number. Suetonius recounts, “Next to the immortal Gods, he honored the memory of the leaders who had raised the estate of the Roman people from obscurity to greatness. Accordingly, he re stored the works of such men with their original inscriptions, and in the two colonnades of his forum dedicated statues of all of them in triumphal garb, declaring besides in a proclamation: ‘I have contrived this to lead the citizens to require me, while I live, and the rulers of later times as well, to attain the standard set by those worthies of old.’”(10) These statues of the summi viri(11) Suetonius describes stood in the eastern portico. The statues were meant to affirm a continuity with the great men of the past and with the Roman republic that Augustus was purported to have restored, maintaining the farcical façade of republicanism that Augustus was so keen to maintain. The statues of the western portico represented the illustrious ancestors of the Julian line to which Augustus belonged—from Julius Caesar, back to Romulus, son of Mars and first king of Rome, to Aeneas, son of Venus and founder of the Roman race.

This relationship is again reinforced by the pediment of the temple. The pediment itself has been lost to the ravages of time; however, the content of its statuary has been preserved in a panel thought to be from the Arch of Claudius. In the center was Mars the Avenger, god of war, father of Romulus, to whom Augustus vowed the temple in exchange for his aid in avenging Caesar and Crassus. To the right of Mars stood Venus Genetrix, mother of Aeneas, patron goddess of Caesar, and founder of the Julian gens(12). Next to her sat Romulus, the deified founder and first king of Rome. Reclining next to him was the personified Palatine Hill, the site of Rome’s birth. To the left of Mars stood Fortuna, goddess of fortune, who had favored Augustus and the Roman people. Seated next to Fortuna was Roma herself, the divine personification of the city. At her side reclined the personified Tiber River. Crowning the temple, above the pediment, would have stood statues of winged Nikes(13) on both cornices of the temple, lauding the victories of Augustus. Within the temple stood the cult statues of the divine ancestors of Augustus, Mars Ultor, Venus Genetrix, and Divus Julius. This central presentation of Augustus, standing in triumph before his divine ancestors and the founders of Rome, declared to all who entered the forum and beheld the temple that Augustus himself was divi filius, son of the divine.

(Figure 6) Ara Pietatis: Fragment of Precinct Wall with Relief of Temple of Mars Ultor. 43 A.D. Marble.

Through this grand display of lineage—underscored by the inscriptions on the base of every statue that detailed the deeds of each of the great men that preceded him—Augustus created a monument chronicling a full, public history of the Roman people, from their humble beginnings atop seven hills to masters of the Mediterranean. An illustrious history, divinely ordained, of which Augustus was the consummation, signified by the presence of his visage atop his quadriga in the center of his forum — a monument whose inscription lauded him Pater Patriae, Father of the Fatherland.


1.  Sanctuary of the temple housing the cult statue.

2.  A roofed, porch-like structure supported by columns at regular intervals.

3.  Pliny, Natural History (XXXVI.102)

4.  The Second Triumvirate a coalition formed by Antonius, Lepidus, and Octavian in 43 BC.

5.  The Battle of the Teutoburg Forest, described as the Varian Disaster by Roman historians, was a major battle between Germanic tribes and the Roman Empire that took place in modern day Germany, resulting in the destruction of three legions and the loss of all Roman territory beyond the Rhein.

6.  The forum built by Julius Caesar.

7.  The title formally used by Augustus, first citizen.

8.  A ceremonial chariot drawn by four horses, associated with triumph and Augustus’ patron deity, Apollo.

9.  A semicircular recess, in this case used to house courts of law.

10.  Suetonius, Lives of the Twelve Caesars, The Life of Augustus (31.5)

11.  Greatest men.

12.  A group of families in ancient Rome who shared a name and claimed a common origin.

13.  Greek goddess of victory.


Witnessing a Fragment

One of the specialties of the Institute of Oral History (IOH) at The University of Texas at El Paso (UTEP) is gathering and memorializing the experiences of individuals in the Bracero Program. The Bracero Program (1942–1964) was the largest temporary worker program in U.S. history, bringing Mexican men to The United States to work in agriculture.


Literature for Everyone: Unanswered Questions

October 1, The University of Texas at El Paso

Border University Collaborations: Past, Present, and Future

November 1, The University of Texas at El Paso