Two crowded processions of personages parade along the north and south sides of the Ara Pacis; they are priests, cult attendants, magistrates, and also women and children, whose historical identity can only be hypothetically and tentatively ascertained. This circumstance is, of course, due to the fact that, over the years, different characters have been recognized in the same figures. But, above all, uncertainty comes from new research demonstrating that the assembly of the slabs composing the processional frieze should be reconsidered to make room for at least five more characters that, so far, had been ignored: three on the northern side and the other two on the opposite side of the relief (Foresta 2002). Also the action performed by the procession is still unclear, even if the plausible assumptions are basically two: the first interprets the scene as Augustus’ reditus, the reception ceremony offered to the princeps upon his return from his long stay in Gaul and Spain; the second hypothesis reckons that the moment shown is that of the inauguratio of the Ara Pacis itself, the ceremony delimiting and consecrating the space where the altar was to be erected. It is remarkable that, whatever the case, we would be presented with events that took place on the same date, that is on 4 July 13 BC. Notwithstanding the manifold problems implied, a considerable series of studies and academic debates that have developed throughout more than a century, have allowed to provide, at least for this part of the frieze, a rather accurate and—in several points—convincing description of the personages depicted and of the public and religious authorities attending the ceremony. To start with, it is quite certain that the two rows of characters on the two sides of the precinct illustrate one single procession. This implies that the two friezes must be considered as a whole, in other words, as if one was watching the procession from both sides of a street. It can be noticed that on both the reliefs the characters are moving from east to west, towards the main entrance of the Ara. In both cases the parade is opened by the lictores (north 1, north 2 and south 3, south 4), then it goes on with the representation of the priestly Colleges and probably of the highest town magistracy, and is concluded with the dynastic picture of the Augustan family, using the same visual arrangement on both sides of the precinct. On the south side, one of the few characters whose identity is undisputed is Augustus (south 15); he is portrayed as a priest, with his head veiled and wearing a laurel wreath. Around Augustus the procession seems to come to a halt, all the personages turn their head and their eyes on him: the whole scene seems to find its climax in the figure of the princeps. Unfortunately the loss of the left hand and of almost the whole right side of the figure, with the exception of an important fragment of the forearm, does not allow us to understand clearly what action Augustus is undertaking in such crucial area of the relief, the visual focus of the procession. Therefore, the scene needs to be set in the wider context of the relief as a whole. Following Augustus are the four flamines maiores, easily recognizable by their typical leather hat (galerus) with a metal point on top (apex). In Rome, in 13 BC, there were sixteen flamines who superintended on the cults of as many divinities, but only the most important four of them—those in charge of the cult of Jupiter, Mars and Quirinus, the main Roman triad, plus the flamen lulialis (south 22) who attended the cult of deified Julius Caesar—belonged to the patriciate. Here their rank is confirmed by their wearing the typical patrician boots, the calceus patricius. This kind of shoe was bound to the leg with thongs, characteristically tied and fastened around the calf. Among the flamines, other than the flamen lulialis, one can surely recognize also the flamen Dialis (south 23), the assistant at the cult of Jupiter, who is holding in his right hand the commoetaculum, a staff used to keep at a distance the people attending the ceremony. His dignity is attested also by the presence of the flaminius lictor (south 25), the assistant following him with the ritual axe on his left shoulder.

With the Vestals, the rex sacrorum and the pontifices proper, the flamines constituted the collegium Pontificum, one of the quattuor amplissima collegia, the four most important priestly orders of the State’s religion. Of course, the other three orders—the quindecimviri sacris faciundis, the septemviri epulones and the augures—are represented at the head of the procession that unwinds along the Ara’s precinct as well. The identification of the quindecimviri and the septemviri is provided by the presence of the relative cult assistants, the camilli, who carry ritual equipment and symbols of the order to which they belong. The quindecimviri can thus be identified on the north side, from figures north 21 to north 30, gathered around the camillus (north 23) holding a small jug in his right hand (urceus) and a casket (acerra) in his left. Since the quindecimviri, in charge on the foreign cults and keepers of the Sybilline books, were connected with the cult of Apollo, one can notice that Apollo’s tripod, flanked by two figures bringing offerings on trays (lances) is represented on the acerra. On the north side (figures north 3 to north 13), one can recognize the septemviri, the priestly college in charge of the senatorial banquet, the ceremony that concluded the sacrifice to Jupiter; they were also responsible for the banquets offered to the people on occasion of the games. The young attendant following them (north 7) brings an acerra on which the sacrifice of an ox before a togaed and of a victimarius is illustrated. In his left hand the camillus holds a patera for the offerings libation. The presence of the pontifices (south 5 to south 11), the third of the priestly colleges whose offices implied sacrifices, was recognized on the south side. Consequently they are accompanied by a camillus (south 9) who brings an acerra as well. This casket, however does not bear characteristic ornaments. Unfortunately the loss of the left hand of the attendant prevents us from being certain, but he is very likely to have held the simpulum, an instrument with the shape of a ladle with a long handle, that was used by the pontifices to libate wine during the sacrifices. Therefore it remains to locate the fourth major priestly college, that of the augures, who did not perform sacrifices and cannot therefore be identified through their relative attendant. Their fundamental importance comes from the fact of their being the interpreters of the gods’ will and in particular of Jupiter. They have actually been recognized both on the north (figures from north 15 to north 19) and the south side (figures from south 14 to south 18), in the group surrounding Augustus. The hypothesis that the figures gathering around the princeps are the augures cannot be accepted without hesitations and cannot be taken for granted. Effectively, the identification of the fourth of the major colleges depends on the interpretation of the entire procession. In fact, if one understands the scene as the ceremony celebrating Augustus’ reditus from the western provinces, then the characters gathering around him are likely to be the consules, Tiberius and Quintilius Varus, and the magistrates in office in 13 BC. On the contrary, if the scene is to be interpreted as the altar’s inauguratio, then the presence of the augures becomes an essential element near the figure of the princeps, who is portrayed in the most dramatic moment of the altar’s foundation. In the Roman ceremony the inauguratio followed immediately the decision to erect a sacred building: the chosen site was ritually delimited by the augures, who pronounced the traditional formulae to “free” the place from any earlier or haunting presence and consign the area to the jurisdiction of the god to which the altar was dedicated. If this interpretation is correct, the right hand of Augustus should be completed with a lituus, the crooked staff by which the augur marked the heavenly and earthly borders of the chosen site. Those who support this theory (Pollini 1978) also think that the shape of the surviving right forearm well suits the action of the augur, both because of its outstretched position and because the hand is clenching on an elongated object, like a lituus. When the sacred space was delimited by the augures, generally the pontifices would immediately proceed to its consecratio. The procession would then represent the actual act of foundation of the Ara, its constitutio, and would also explain the presence, on the internal face of the precinct, of the planks ornamented with garlands and bucrani (ox skulls) to temporarily fence the inaugurated space. However, there is an equally plausible interpretation of the scene. This hypothesis sees the procession as an idealized climax of Augustus’ reditus from the western provinces. In this case the scene depicted is a topical one, that precedes, in time and order, all the other representations of the Ara Pacis. All the gestures and the glances that the characters focus on Augustus should then be interpreted as a “welcome” from the State’s authorities to the man bringing peace and prosperity to Rome. Even Augustus’ outstretched right arm could be intended as a salute, even if actually he is not answered by the character facing him, who keeps his arm stretched along his side, as evidenced by the position of the surviving part of the elbow. This interpretation would not clash with the statement of Cassius Dio (LIV, 25, 4) who refers that upon such circumstance, as well as when he returned from the eastern provinces in 19 BC, Augustus entered Rome at night to avoid the throng of the jubilant crowd. The Ara Pacis would therefore “symbolically depict the reditus in its wider meaning, as an official act of rule, pervaded with a religious and timeless atmosphere”; in this way the procession of the Ara is “a supratemporal presentation, sub specie aeternitatis, of the homage paid to the princeps, who comes back to his country bringing with him happiness and a new golden age, according to a widespread symbolical tradition in the Hellenistic world” (La Rocca 2002).