The adlocutio scene depicts a typical episode of the emperor motivating his troops at the beginning of a military campaign. His left hand, now missing, probably held a lance. His right hand is raised in gesticulation. Seven soldiers, each in different types of uniforms, including scale armor and chain mail, listen intently to their leaders words. The top part of the panel, including the tops of the standards, is a restoration.

The adventus panel is generally agreed to represent the return of Marcus Aurelius from battle after his successful campaign against the Germans and Sarmatians in 176. P. G. Hamberg referred to this scene as "allegorical", a term that did not sit at all well with Karl Lehmann. Hamberg's basis was that Marcus is the only mortal character in it, although it seems to represent a real location, the Temple of Fortuna Redux on the Via Latia in the Campus Martius. Its primary focus is the interaction between Marcus and Roma on the right side. Mars stands behind the emperor; the war is over. Victory flies over Marcus's head, above two lesser deities or personifications in the background.

A crowd stands aroung Constantine in the Rostra with the Arch of Septimius Severus behind them.

Citizens gather near the Basilica Julia.

Constantine's victory is a fait accompli with the presence of Victory and Virtus. Constantine, now missing from the frieze, was in the boat immediately to the right of the River God, adjacent to the bridge at bottom left. His enemies are drowning in the river Tiber, having been overtaken by Constantine's soldiers along the top of the frieze. Musicians celebrate the victory at far right.

One of eight Dacian captives, standing proud and handsome across cornices around the attic, may have come from Trajan's Forum, which was bounded by a large frieze discussed below. The statues undoubtedly date from the period from Domitian to Trajan, since they clearly portray Dacians. Carved in pavonazzetto marble, similar statues have been found in Trajan's Forum, including one on display in the Vatican's Braccio Nuovo. One of the Dacians is a modern replica. The remainder have restored hands and feet.

The clementia panel shows Marcus Aurelius seated on a tall stool (sella castrensis) with his right-hand man Pompeianus standing at his side. Soldiers with flags and standards surround two barbarian prisoners, an exhausted older man and a young boy who props him up. Some writers have concluded that this is a barbarian chieftain and his son, who, full of grief, are subjugating themselves. This panel also appears to bear the mark of Commodus's damnatio. The center of three standards (an imago) holds two portrait images. The uppermost of these is in good condition, but the face on the lower one is completely worn or chiseled away. Differential erosion seems unlikely. Eric Varner noted that the subject of the lower one appears to be cuirassed and includes a paludamentum, the cloak worn by a Roman general. Thus, as Wegner suggested, the two portraits probably originally showed Marcus and Commodus, with Commodus having been intentionally obliterated.

Note the use of hierarchy of scale, an artistic device that became popular in Chrstian art; Constantine is much larger than his soldiers.

The short eastern side of the frieze, now heavily damaged, shows the triumphant emperor's entry into Rome, although it clearly is not depicted as a triumphal procession. He sits on a throne (cathedra) that is part of a quadriga.

Constantine is the only figure in this scene to be shown completely frontally. Surrounded by men in togas, he takes center stage. This hieratic representation of the emperor on high suggests a new concept of sovereignty and lordship (dominus), a near deification of Romes first citizen. This trend toward divine worship began with Augustus and would continue through the reign of Theodosius I. The impact of this representation of the emperor on the imagery of Christ Pantocrator in Christian art is the subject of considerable scholarly debate.Details of the Rostra and its surroundings are clearly identifiable. The Basilica Julia can be seen on its left side, with the Arch of Septimius Severus on its right. Five columns appear directly behind the Rostra. Diana Kleiner identifies these as belonging to the monument of Diocletian's Decennalia. Constantine appears between two statues on pedestals. On viewer-left is Marcus Aurelius, seated and wearing a toga. The other statue depicts Hadrian, with typical hair style and beard, holding a globe in his right hand. This setting informs viewers that Constantine belongs to the line of great emperors from the past. He thus differentiates himself from his immediate predecessors, the tetrarchs. Some writers have also suggested that the three young boys in the scene, uncommon in state sculptures, were meant to foster the idea that Constantine, who had three sons who were Caesars, would return to a dynastic succession model.

The last scene in the great frieze of Constantine recalls Marcus Aurelius in the liberalitas attic panel, overseeing the distribution of gifts to the public. Again Constantine is in the exact center of the frieze, this time seated on a podium (his head is missing). The similarity of Christian depictions of the throned Christ surrounded by disciples to this Constantinian scene - intentional or coincidental - is obvious. Constantine's right hand holds a tessera with slots for coins, some of which are falling out to be caught in the toga of a senator who gazes up at his benevolent leader. Four small rectangular scenes are enclosed within the borders of the frieze. These all depict distribution of money and the associated record-keeping.

Hadrian, the likely hero of these roundels before they were recarved in Constantine's time, was particularly fond of hunting.

The poor fit of pre-carved components seen on the Arch of Constantine suggests that the structure is unlikely to be earlier than the time of Constantine. The comparatively poor workmanship seen in this shape mismatch in the entablature would have been unthinkable on any Hadrianic or Domitianic monument.

Sol in his quadriga, a four-horse chariot.

See also the discussion of the related roundel on the west end of the arch.

IMPERATORI CAESARI FLAVIO CONSTANTINO MAXIMO PIO FELICI AVGVSTO SENATVS POPVLVSQVE ROMANVS QVOD INSTINCTV DIVINITATIS MENTIS MAGNITVDINE CVM EXERCITV SVO TAM DE TYRANNO QVAM DE OMNI EIVS FACTIONE VNO TEMPORE IVSTIS REMPVBLICAM VLTVS EST ARMIS ARCVM TRIVMPHIS INSIGNEM DICAVIT To the Emperor Caesar Flavius Constantinus, the Greatest, pious, fortunate, the Senate and people of Rome, by inspiration of divinity and his own great mind with his righteous arms on both the tyrant and his faction in one instant in rightful battle he avenged the republic, dedicated this arch as a memorial to his military victory.

This scene of public largess is most likely associated with the liberalitas of 177, centered upon Marcus Aurelius and his son Commodus after their joint victory of 176. Pompeianus is present, but Commodus is not. A conspicuous void in the relief probably reveals where Commodus once sat on a sella curulis like his father. A fragment, likely the remains of his foot appears on the podium. Further evidence of recarving of this part of the relief is the fact that the bottom half of the toga of the man standing on the step is carved in lower relief than that of his upper half, and that this difference is not easily explained by differential weathering of the panel. Several of the heads are restorations. The head of a boy riding piggyback on his father’s shoulders is missing. The surface finish of the recarved area is also noticeably rougher than that seen in the rest of the relief. Commodus, subject of a damnatio memoriae, also appears to have been removed from one of the related panels on display in the Capitoline Museum.

Lustratio is a celebration with the army at the beginning of a military campaign, probably originally referring to ritual purification before battle. The emperor presides over the ceremony, using a portable tripod-mounted altar. A bull, sheep, and pig will be sacrificed in a rite called the suovetaurilia, in which Mars would be expected to purify the land. Soldiers with flags and ensigns stand behind a musician and an incense bearer (camillus). Pompeianus appears behind Marcus/Constantine, with his head above that of the bull. The upper quarter of the panel, showing tops of the wreaths and the eagle atop the standard, is a restoration. The portrait in the imago on the left is too weathered to support identification of its subject. Art historians frequently debate the style of the lustratio scene. Most agree that it represents a more modern departure from the styles of the other seven panels on the arch.

Constantine has defeated "the tyrant" Maxentius.

This panel depicts enemy soldiers dragged before the emperor in the field, as indicated by the tree on the right side of the image. One of the captives is still resisting while the other has accepted the futility of doing so. The emperor wears a tunic, a paludamentum and leggings. Once again, Pompeianus, similarly dressed, stands beside him. The panel has been broken in two and repaired.

This profectio scene, likely from a lost arch of Marcus Aurelius, probably represents Marcus's departure for battle in 169. The emperor wears a traditional short tunic and mantle, the heel of his right foot lifted to signal impending motion. A reclining personification of the road Via Flaminia in the case bids him farewell. The identification of the personified road - odd as this sounds - is certain; coins of the era depict parallel scenes where the relevant roads are actually labeled. Virtus, dressed for travel as compared to the nearly identical Roma, who usually bears one breast, will presumably accompany the emperor into battle. A genius senatus, bearded and wearing a toga, stands behind Marcus. A man, usually agreed to be Claudius Pompeianus, Marcus Aureliuss son-in-law and advisor, stands to his left, barely visible in this relief. Earlier scholars, such as Stuart Jones and Eugenie Sellers Strong identified this assistant as Bassaeus Rufus instead of Pompeianus, who seems to be generally accepted today. Wegner considered this relief to be in the klassischer style, however the treatment of soldiers and horses does not seem to fit that description. L'Orange identified the structure in this scene as the Arch of Domitian in the Campus Martius. Note that the arch is crowned with a chariot drawn by elephants.

The south face attic begins with a Rex Datus scene, wherein a vassal king is either crowned before or introduced to the Roman soldiers. The event indicates that a peace treaty has been signed and that a former enemy is now an ally. Early scholar Giovanni Bellori, who examined the piece in 1690, also saw it as showing coronation of a vassal king, although he concluded that the emperor was Trajan. Frothingham concluded that the original emperor was Lucius Verus, on the grounds that no coins of Marcus Aurelius depict a Rex Datus, whereas several coin types of Verus do, including legends such as rex armeniis datus. One minor peculiarity of the scene is the lack of the kings subjects, who would have witnessed such a ceremony, possibly omitted simply due to space constraints. The head of the king is a modern restoration.

The recarved emperor in this scene is clearly not the same as the one in the preceding roundel; reasonable candidates are Constantius and Licinius.

Constantius, like Maximian, claimed to be a descendant of Hercules. A small figure of Victory appears at Hercules left side.

Constantine's men, possibly shown in primarily-defensive posture for propaganda reasons, confront an enemy at the city walls.

A statue of Hadrian, with typical hair style and beard, holding a globe in his right hand.

This releif seems to depict a real location, the Temple of Fortuna Redux on the Via Latia in the Campus Martius.

The figure at top left of this first roundel on the north face appears to be Antinous, although in atypical clothing. The recarved emperor's head in this scene is easily identified as Constantine.

The frieze begins at the left edge of this composite image, where Constantine in his chariot departs Milan to attack Maxentius.

The emperor in this scene does not appear to Constantine. It may depict Licinius.

This is one of four large reliefs (east and west attic and two central interior bays), that probably originated in a 30 meter long frieze in the Forum of Trajan. Most authorities agree that they originally depicted Trajan and date to early Hadrianic times. Others have concluded that Domitian was the subject of some of the reliefs, and that they somehow, like the Cancelleria reliefs, escaped mutilation during the two short periods of Domitian's damnatio. One objection to their originating in the Forum of Trajan is that it was reported to be still intact in the time of Theodoric, long after the Arch of Constantine was built.

This relief on the east end of the arch at attic level, including buglers, Romans on horseback, and several falling or fallen Dacians, is a battle scene from the series of Dacian wars that ended in 106.

One of four large reliefs (east and west attic and two central interior bays), that probably originated in a 30 meter long frieze in the Forum of Trajan. It depicts an ambush, showing that the crude weapons of the Dacians are futile against the advanced weaponry and armor of the Romans.

Constantine observes the vicrorious siege of Verona.

This roundel, like the one on the other short side of the arch, is noticeably different from those on the north and south faces. Unlike them, its circular bottom edge has not been reworked; and its style and content is different. Art historians in the early 20th century were quick to point out the poor quality of these roundels in comparison to the earlier sculptures. Modern critics acknowledge that the Constantinian artists had a less realistic style; but the notion that a decline in artistic quality was a consequence of hard times in the empire is incorrect. Associating a decline in structural workmanship with hard times, on the other hand, appears to be valid.

The roundel shows Luna in her biga, a two-horse chariot. The moon image is placed above a section of the giant frieze of Constantine (described elsewhere) where Constantine's first son, Crispus is shown in military triumph. Some have suggested that this arrangement was intentionally meant to describe Crispus as a reflection of Constantine as the moon is a reflection of the sun. Bill Thayer notes the irony of this metaphor: the moon, once full, wanes to nothingness, which is exactly what happened to Crispus.