This fragmentary plaque once formed part of an altar dedicated to Jupiter Optimus Maximus, in the Roman colony of Martia Iulia Salonae in Dalmatia (Solin, modern Croatia). Although one side of the original text is missing, the plaque itself was reconstructed in the mid 1500s according to an earlier manuscript edition of the inscription’s text; it is an important source for understanding how Roman religion functioned in the provinces in circumstances in which the civic authority of Rome had not been fully established, or when it served a community of disparate and divergent allegiances.

 

The inscription reproduces the actual words that were spoken at the dedication of the altar, following an initial praescriptio (preface, or introduction) that gives the names of the consuls of Rome, Lucius Aelius Caesar and Publius Coelius Balbinus Vibullius Pius, and the date (9^th October 137 CE). The next name mentioned, Caius Domitius Valens, is that of the leading municipal figure in the town, the duumvir iure dicundo, the highest judicial magistrate, who will have presided over the actual event of the setting up and dedication of the altar. The inscription states that it was he who “gave the words” that are recorded there below (dixit in ea verba quae infra scripta sunt). The dedication itself is given in the first person, as a verbatim record of what was said; it states that the altar was given and dedicated to Jupiter Optimus Maximus (Iuppiter Optime Maxime…aram dabo dedicaboque), and that it is dedicated according to a set of “laws” (ollis legibus) that govern its regulation. These “laws” were the conditions that determined how sacrifices and offerings should be made at the altar, as individual requirements of a more general, empire-wide statute (Laffi, “La Lex Arae Iovis Salonitanae”, p. 123). As well as legal regulations, the dedication also specified the boundaries of the sacred area within which the altar was set (uti infimum solum huius arae est); Theodor Mommsen believed that these words referred to the boundaries of the altar being where the ground levelled out, but Carin Green has refuted this, preferring instead to understand infimum solum as indicating the physical territory upon which the altar was set. She suggests that the ‘sacred space’ was conceived to be three dimensional, and “included the trees and air above the circumference of the boundaries” (Green, Roman Religion, p. 96, n. 19, contra Mommsen, CIL III, 1933). Umberto Laffi has noted that this statement of the boundaries of the sacred space is, in fact, formulaic, with previous evidence for it given by the altar dedicated to Augustus in Narbonensis (see Altar of Augustan Peace at Narbo (CIL XII, 4335); Laffi, “La Lex Arae Iovis Salonitanae”, p. 123-4). Further similarities with the altar at Narbonensis occur in the following line of the inscription, in which the regulation of practicing sacrifices is given. The text states that when a sacrifice is made that does not also produce the magmentum – the entrails of the sacrificial victim – as a supplementary offering, the sacrifice itself should still be conducted in the regular way, indicating that there was a ‘proper’ process to sacrifice that the state sought to regulate across the empire, and which continued to be monitored according to the law.  

The most important statement of the altar’s religious and legal propriety occurs in lines 7-8 however, in which the dedication promises that “the rest of the laws for this altar be the same as those given for the altar of Diana on the Aventine Hill” (ceterae / leges huic arae eaedem sunto quae arae Dianae sunt in Aventino monte). The regulations given for the cult of Jupiter Optimus Maximus in Dalmatia were, then, instructed to be exactly the same as those of a particular cult of Diana in Rome, indicating a symbolic link between the religious practices of the province and the centre. Diana’s cult in Rome had led to a lex arae Dianae in Aventino, an ancient law reportedly established by Servius Tullius, the legendary 6^th king of Rome, which continued – even here in the second century CE – to be invoked in regions of the Roman world where people had to act together, but did not necessarily belong to the same community (Green, Roman Religion, p. 95. For the origin of the cult of Diana on the Aventine, see ibid, p. 97-111; Malaspina, “Diana Nemorensis vs. Diana Aventinensis”, p. 15-35). The law itself has not survived to us, and is known only from epigraphic evidence such as the inscription under discussion here, but it was clearly used as a way of standardising religious practices amongst groups who lacked an established civic structure – including priesthoods – that would allow them to make a conventional dedication (Green, Roman Religion, p. 95). The law was used to define the physical boundary of a sacred space, and to determine what kind of religious behaviour, such as the ritual of sacrifice, was appropriate within it. However, as Carin Green has rightly noted, the lex arae Dianae was not used in order to promote federalism, or the equal participation of all members of a community in a particular cult, irrespective of their different origins; the lex arae Dianae was, rather, used to supervise ritual dedications in circumstances in which civic authority did not apply (Green, Roman Religion, p. 96-7). This is interesting if we consider the location in which the altar was originally dedicated, namely the colonia Martiae Iuliae Salonae, in modern Croatia. As the name of the place indicates, the settlement was organised as a military colony under the Julio-Claudians; not only does it bear their name – Iulia – but it also bears the epithet Martia, derived from Mars, the supposed ancestor of the Julian gens (Laffi, “La Lex Arae Iovis Salonitanae”, p. 126). There is some debate as to whether the colony was inaugurated by Julius Caesar or Augustus, but it is clear that it was not a new settlement at the time that the altar was dedicated, potentially a century later (for the foundation of the colony, see Wilkes, Dalmatia, p. 221-224). It is extremely unlikely that over the course of one hundred years the Roman administration had failed to establish a civic infrastructure in Salona; indeed the fact that it was the duumvir iure dicundo, the chief judicial magistrate, who made the dedication recorded in the inscription would suggest that the government of the colony was organised in accordance with regular municipal practice. In this respect, invoking the lex arae Dianae would appear to be unnecessary in as far as it applied to situations in which civic law was not yet established. However, the final lines of the inscription reveal more: Caius Domitius Valens states that he gives and dedicates the altar precisely so that Jupiter Optimus Maximus will look “favourably” (volens propitius) upon him, his colleagues, the decurions, the colonists and the inhabitants of the colony of Martia Iulia Salona, their wives and their children (mihi collegisque / meis decurionibus colonis incolis coloniae Martiae Iuliae Salonae coniugibus liberisque nostris). The colonis and the incolis – the colonists and the inhabitants – represent two groups with “potentially conflicting allegiances”, who could not perhaps be brought together under a common religious dedication; even one century on from the colony’s foundation, the local population, who may not have yet gained Roman citizenship, might have continued to foster religious practices specific to their native gods, which were not in Rome’s interests, or habit, to dictate (Green, Roman Religion, p. 96).  The erection of an altar to the most powerful of the Roman gods that was subject to a specific legal framework, and under which all were now constrained to operate, allowed the Romans to continue to promote their gods in a way that was clearly defined both in terms of the physical space of the colony – regarding the boundaries of the sacred area – , but also in relation to the common sacrificial practices that were shared with the capital city. The fact that Jupiter’s protection was invoked in the name of all the inhabitants of the colony, citizen and non-citizen alike, supported Rome’s ideological presentation of the gods as benevolent, generous, and also unequivocal. Whether the local inhabitants of Salona had come to terms with Roman occupation or not, the invocation to Jupiter in the form of the altar and its dedication advertised the supremacy of Rome’s political and religious position. The application of Rome’s laws to how that religious superiority was performed not only connected the colony and the wider province to the capital city, but also promoted the image of her religious and legal systems as ones that were imbued with constitutional propriety and integrity, particularly with regard to the safety and security of all those in her power.