One of the main concerns that emerges from the inscriptions is the connection between legitimacy and family continuity in the Achaemenid line, named for Achaemenes, the oldest ancestor given by king Darius I in his genealogy (DB §1-5). Kingship in the Achaemenid Persian Empire was hereditary within this line and descent by Achaemenid blood was thus the essential foundation of kingship all the way to the end. As a rule, the succession seems to have been settled by the king's designation (Hdt. 7.2.1), though exceptions do occur. Usually the designated heir was the first-born son, and only occasionally the son born first after accession, a precedent established by Xerxes I (Hdt. 7.2f.; XPf §4), or the first son born of an Achaemenid blood union (Plut. Art. 2.4).
This preoccupation with dynastic legitimacy is made manifest both explicitly, particularly by Darius I and Xerxes I, and implicitly throughout the corpus of royal inscriptions. The implicit insistence on family continuity and Achaemenid blood is tangible in the patrilineal litany that introduces the king as the agent in almost every inscription. With obsessive insistence, the kings repeat the last element of their genealogy, Haxāmanišiya, "an Achaemenid", a word that encapsulates the unbroken chain of father-son relations recorded in the genealogical formulae. Together with the favour of Ahuramazda, this genealogy is what qualifies the speaker of the inscription as king, who can then proceed to document the agency he has displayed in this capacity. Any Achaemenid royal inscription therefore serves to reinforce these three pillars of legitimation: bloodline, divine favour, and the ability to shape the world through great works.
The stemma of the Achaemenid dynasty is complex (Rollinger 2017), because it seems clear that the first two kings of the Persian Empire, Cyrus and Cambyses, did not see themselves as Achaemenids. In the most important surviving document of his government, the "Cyrus cylinder" from Babylon, Cyrus II refers to himself as "King of Anshan" and there is no mention of an Achaimenes as an ancestor, only of Cyrus' grandfather Cyrus I and his ancestor Teispes (C²Ba §7; Waters 1996, 11-15). Unfortunately, no inscriptions of his son Cambyses have been preserved that could confirm this view, but he and his father are sometimes described as Teispids nonetheless. When Darius I ascended the throne, the inscriptions he set up ostentatiously claimed kinship with Cyrus (Briant 2002, 107-114; cf. Frye 2010; Henkelman 2011 on the common ground between the two).
Right at the beginning of the great Behistun inscription, Darius gives his ancestral line in far greater detail than had been customary on 6th century BCE royal inscriptions, such as the Cyrus cylinder and other Neo-Babylonian royal inscriptions (DB §3-5). By doing this, he succeeds in incorporating Teispes into his stemma, but goes back one more generation to an Achaemenes, thus asserting the superiority of his chosen ancestor over Cyrus'. The following lines make it clear that this listing is intended to emphasize continuity with Cyrus and Cambyses, underscore the persistence of their dynasty in a different aspect, and communicate the historical depth of Darius' claim to the throne. Together with the historical murkiness of Darius' accession itself, the peculiarities of this genealogical model and its exceptionally ostentatious presentation undermine the credibility of this ancestral lineage. Such scepticism is reinforced by the fact that inscriptions by Cyrus found at Pasargadae (CMa-c), in which he calls himself an Achaemenid, were most likely commissioned by Darius because they are in Old Persian script, which was created only under him (Briant 2002, 126), and the fact that Cyrus does not call himself an Achaemenid in the Cyrus Cylinder (Stronach 2000; Schmitt 2007, 28-31). While there were important parallels and continuities between Teispids and Achaemenids (Henkelman 2011), one should thus bear in mind that the Achaemenid kingship proper, as it is presented in the inscriptions, is a creation of Darius and his successors. The need of Darius I and his successor Xerxes I for explicit, monumentalised formulations of their right to rule and their adoption of a bloodline ideology derives from Darius' lack of such clear-cut dynastic legitimacy and the weakness of his successor's position, who was not the first-born son, but the first son born of Darius' union with a daughter of Cyrus.
Besides its insistence on ancestry and dynastic continuity, the royal self-description developed by Darius contains an ethnic affiliation (Persian) and a self-definition as "Aryan of Aryan stock" (XPh §2, DSe §2, DNa §2; cf. DB §70; the Elamite version of Behistun (§62f.) names Ahura Mazda as the Aryan god). The OP word arya refers to the Indo-Iranian lineage of the so-called Iranian peoples, which connected tribes such as the Medes and Persians (Hdt. 7.62; Strab. 15.2.8). The close connection expressed by arya is echoed by the prominent position of Media in the inscriptions (e.g. DNa, DPg, DSe, XPh) and the important role of Median traditions in the Empire (Briant 2002, 23-28). The usage of arya as part of the heritage that qualifies the king's bloodline to rule further functions to underscore the exceptional place of Persia in the Achaemenid worldview: no non-Iranian could rule the Achaemenid Empire (Briant 2002, 180-182).
Already during Darius' reign, some degree of separation between the Persian aristocracy and the ruling family seems to have been established. While intermarriage between the Achaemenid royal house and Persian aristocratic houses occurred, only the main wives of Xerxes I and Artaxerxes II, Amestris and Parysatis, seem to have been drawn from the nobility, in both cases because their fathers needed the support of the nobility. The more usual course of action was for the king to marry an Achaemenid queen, such as a half-sister; while full sisters are mentioned in the Greek sources, the veracity of this material is questionable (Brosius 1996, 45f., 66f.). There was a distinct effort to keep the Achaemenid bloodline 'pure' so as not to allow other aristocratic families access to Achaemenid blood in the male line. Beyond the main queen, however, the king married for a variety of reasons and was not much restricted in his choices. Especially "illegitimate" princes and princesses were nonetheless frequently married off to establish bonds both with Persian nobility and with other members of the imperial elite and beyond. Such marriage alliances were used especially by Darius I to bolster his legitimacy (Hdt. 3.88.2-4, 7.2.2; Brosius 1996, 47-64). The reciprocal exchange of proportional and carefully stratified gifts was another means used in creating a differentiated hierarchy between the royal house and the aristocracy, which bound members of the leading families to the king as individuals, even without family ties (Briant 2002, 137, 352-354).
Darius' immense efforts to justify his kingship were not necessary for his successors, at least not on the same scale. What was necessary was to prevail over competitors who were similarly qualified for the throne, so successful or favoured princes born of the king's main wife (Schmitt 1983). Establishing continuity was crucial to mark this success and the epigraphic formulae created by Darius remained in use in the following generations with only small deviations.
It was Darius' son and successor Xerxes who felt the pressure to smooth the transition most heavily, as is clear from the wealth of inscriptions he left behind, second in number only to those of his father. Like his father, he titles himself king of kings, protégé of Ahura Mazda, and above all an Achaemenid (e.g. XPa-b). Together with the paternity of Darius, this suffices as genealogical information in the inscriptions of Xerxes, which only rarely add the ethnic identifiers as Persian and Aryan (XPh). This may indicate just how important a change had been established by Darius' reign, since Xerxes could have called himself a descendant of Cyrus through his maternal line, but no women are ever mentioned in monumental Persian royal inscriptions.
The concepts of kingship established by his father are also confirmed in many inscriptions of Xerxes. XPl is essentially a copy of Darius' catalogue of virtues (DNb), which emphasizes the qualities of righteous rule, divine favour and the Great King's abilities in combat and at court (Schmitt 2009, 21). Such repetition of the ethics of kingship, which created a strong parallel between the new king and Darius, was intended to stress continuity in all things. With his building projects, Xerxes likewise followed a line laid down by his father. XPc, inscribed in three copies on the Tacara built at Persepolis by Darius, names the buildings of Darius in the same breath as those of Xerxes. XPa, the inscription on the well-known "Gate of All Lands", similarly links his buildings to those of his father, and XSd and XVa stress Xerxes' respect for the work done by his predecessor, similar to the inscriptions of Darius at Pasargadae. Under his son's reign, Darius' legacy was hence transformed into a model and heritage worth preserving, rendering it an enduring source of power for the present king. Among the corpus of inscriptions, XPf §3-4 stands out due to its overt discussion of dynastic legitimacy. After tracing his lineage back in the conventional fashion, Xerxes mentions the circumstances of his own succession: As one of several sons of Darius, he received the throne by designation from his father, but also by the will of Ahuramazda. These sections on father and son are connected by the references to the activity of building – what Darius began, Xerxes continued – and then maintaining what had been built with the protection of Ahuramazda. Through Xerxes continuation and enhancement of his father's project of Persepolis, the Persian capital thus replaced Pasargadae as the spatial epicentre of Achaemenid dynastic legitimacy.
The significantly smaller corpus of inscriptions left by the later Achaemenid rulers shows that the principles of dynastic legitimacy expressed in monumentally inscribed form hardly changed over time. Dynastically, for Darius II and Artaxerxes I it was sufficient to refer back to Xerxes, Darius I and their membership of the Achaemenid family. Their building inscriptions likewise refer to the achievements of their predecessors where they are relevant (e.g. A¹Pa-b, D²Sb). In the fourth century, the situation changes somewhat. Certain inscriptions of Artaxerxes II (A²Ha, A²Hc, A²Sa) give the ancestral line up to Darius' father Hystaspes and invoke the protection of Mithra and Anahita in addition to or instead of Ahura Mazda. While the provenance of some of these texts is uncertain and a local reason for this deviation is not impossible, the change may also have a dynastic reason and be due to the conflict between Artaxerxes II and his brother Cyrus over the succession. This struggle may have resulted in a higher need for legitimation for the victorious Artaxerxes. The change would then have been an attempt to underscore both his dynastic and religious legitimacy and bind the Persian elite more tightly to his person specifically through the religious innovation (Kuhrt 2007, 475). His son, Artaxerxes III, whose succession was not as difficult, is even more verbose in presenting his ancestral line in one of his inscriptions (A³Pa), tracing it all the way back to Darius' grandfather Arsames. Since Arsames was not king of the empire, this may seem surprising, but it coincides with the attempt by late Achaemenid kings (probably Artaxerxes III) to create inscriptions on gold plaques in the latter's name (AsHa), reinforcing and exhibiting the great age and strength of the dynasty (Schmitt 1999, 106-111; Schmitt 2007, 25-28). Since a similar tablet was created for the remote ancestor Ariaramnes (AmHa), this represents an insistence on dynastic lineage unheard of since the reign of Darius. At the same time, the emphasis again is not on the actual founder of the empire, Cyrus, or on any earlier Persian traditions, but rather derived from the impetus and the model established by Darius. Maria Brosius' summary is hence apt (2000a, 69): "The successors of Darius I all followed the architectural style he had created with Persepolis, adhering to a royal Achaemenid style, which placed their kingship in a historic context. It was an expression of Achaemenid kingship, in which each king saw himself as a part of a dynastic tradition, perpetuating almost eternal values, as opposed to an individual king who, without tradition, needed to impress his own personal style."
Individual historical episodes and rituals relating to the threshold between two kings have been preserved, mainly from the Greek tradition. Due to a lack of alternatives, the great importance of these source snippets for an understanding of dynastic legitimation in the Persian Empire is diametrically opposed to their low resilience and generalizability. This problem applies less to the designation of the royal successors; while there was probably no Persian law of succession despite what the Greek authors believed, the king's designation did carry some weight and usually fell on the eldest son by his main wife. Only in exceptional cases – as apparently in the case of Xerxes – the first son born in the purple, so once his father was king, was chosen as heir to the throne. Likewise, the idea that princes from Darius II onwards assumed "programmatic" throne names at the time of the assumption of power seems plausibly justifiable (Schmitt 1982). By contrast, the institution of a joint rule of father and designated successor from Darius I to Artaxerxes II, as proposed by Peter Calmeyer (1976) on the basis of the Greek sources, is much more difficult to accept. With the exception of the inscription XPf, the circumstances of the transfer of power are never mentioned in the inscriptions, and even XPf gives no clear evidence in this direction: Thus, although Darius designated Xerxes as his successor, Xerxes was only appointed king after his death. It is certain, however, that the Achaemenid kings employed their sons in a variety of administrative and military roles since the time of Cyrus (Briant 2002, 353f.). Finally, the particularly impressive story about the coronation ceremony of the Achaemenid kings from the Artaxerxes Vitae of Plutarch is also disputed in its authenticity. If the story about a coronation ceremony in Pasargadae with the putting on of the robes of Cyrus is often considered plausible (Plut. Art. 3.1-2), Carsten Binder has emphatically pointed out that no indigenous sources exist which could support this episode, which was only handed down by Plutarch, a 2nd century CE Greek author using questionable sources (2010, 473-479).
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Henry Heitmann-Gordon & Sebastian Zellner
Henry Heitmann-Gordon & Sebastian Zellner, 'Dynastic legitimacy', Achaemenid Royal Inscriptions online (ARIo) Project, The ARIo Project, a sub-project of MOCCI, 2020 [http://oracc.museum.upenn.edu/ario/understandingtheinscriptions/dynasticlegitimacy/]