The Sasanian monarchy has a reputation for being better organised and more centralised than its Arsacid predecessor. But the notion that the Arsacid kingdom was in essence a cluster of largely independent political entities, held together in little more than a semblance of formal allegiance to a shadowy central royal authority, may have its roots in tendentious Sasanian traditions. These treat the whole of the Seleucid and Arsacid periods as that of the ‘petty shahs’ or ‘tribal shahs’ (m¯ul¯uk al-taw¯a’if ) and, in sharp contrast, depict the monarchy established by Ardashir as a coherent and effective political and military power. In the Sasanian sixth-century historical romance, the Karnamag Ardasher i Papakan, the fragmentation of Alexander’s empire into 240 small states is the foil to Ardashir’s expoits; the impression produced by the Khwaday-namag tradition of national historical writing, as reflected principally by al-Tabari, is that Ardashir’s rise to power was in effect a long succession of wars for the unification of Iran.41 Greek and Latin sources give the point of view of contemporary outside observers and help to modify this distorted picture, especially with regard to the Parthian empire. However, even these sources suggest that the establishment of the Sasanian monarchy was a dramatic development, for the drive of a rising new power is all too easily contrasted with the lethargy of the ancien r´egime. The result is a widespread consensus among modern scholars that the Sasanian state was more highly centralised and advanced than its Arsacid predecessor. A more balanced picture emerges from an examination of Sasanian institutions, allowing for the distorting vein of propaganda that runs through many of our surviving sources: the dynasty was new, but many of its structures were inherited. Careful analysis of the epigraphic monuments reveals a strong Parthian inheritance, notably an indomitable nobility whose power was only inadequately matched by a somewhat flimsy central administration. Even the question of the genesis of so monumental an inscription as the Res gestae divi Saporis can be misrepresented when coloured by the presupposition of a central royal government controlling every aspect of its erection. A more realistic view would allow for the employment of the remnants of a Parthian chancellery whose execution of the shah’s instructions was not always in perfect accord with his intentions.42 The territorial extent of the Sasanian empire was vast, but the control exercised by central government was not uniformly effective.43 Evidence for the foundation of cities by the Sasanian monarchs after Ardashir, based chiefly on the detailed data preserved by al-Tabari, indicates that their activity was confined to a fairly limited area – the provinces of Fars,Meshan, the Sawad and Media – which were basically the territories conquered by Ardashir I during his wars against the Arsacids and the m¯ul¯uk al-taw¯a’if under their aegis. As a general rule, the Sasanian shahs did not encroach on those territories held by the great lords of the realm, some of whose lineages reached far back into the Parthian era. The one exception to this rule was the occasional establishment of cities in newly acquired border zones, where the shah’s lordship by right of conquest could not be contested; or in remote provinces where royal authority was being re-established. Examples of this exception are the cities founded by Peroz following his war against the Hepthalites: Ram Peroz in the region of Rayy; Roshan Peroz on the border of Gurgan and the Gates of Sul; and Shahram Peroz in Azerbaijan.44 Foundation of a city represented a substantial investment of manpower and resources, and shahs only undertook this in places where it would benefit them, and not one of their overmighty nobles. The picture of a well-ordered hierarchical society, controlled and regulated by a strong monarchy, needs to be reassessed. It emerges from later literary sources of the Islamic period, such as al-Tabari, al-Mas‘udi, Pseudoal- Jahiz45 and The letter of Tansar. The latter is attributed to the powerful third-century herbed Tansar, but was probably composed three centuries later and is preserved in Ibn Isfandyar’s Ta’rikh-i Tabaristan, a problematic source.46 However, these complex issues can be avoided, as the epigraphic sources from the earlier Sasanian period – notably the third century and first half of the fourth – anticipate and corroborate our later literary sources. The inscriptions suggest that the framework of a social hierarchy had already been formally established under Shapur I. The highest rung, immediately below the ‘king of kings’, was that of the shahrdaran. These virtually independent shahs, whose numbers seem to have been much lower under the Sasanians than the Arsacids, tended to be senior members of the royal dynasty and officially ruled their kingdoms as royal appanages. Below them ranked the vaspuhragan, apparently princes of the royal family who held no official post in the royal court. Third in rank were the vuzurgan: members of the great noble houses, including Suren, Karin and the Lords of Undigan, among others. As late as c. 500, the unruly heads of these houses admitted only a nominal allegiance to the central power, and were virtually independent in their hereditary territorial domains. The fourth and the lowest rung documented in the inscriptions was the azadan, minor gentry of free status, and distinct from the other nobility, but probably also dependent on them in many cases. From this lesser nobility were recruited the mounted warriors, asavaran, who made up the core of the Sasanian army.47 These may be identical with another category, that of the kadxvadayan, who occupy a place above the azadan and belowthe vuzurgan in the lists of the Paikuli inscription.On the other hand, they may be an especially favoured group among the asavaran, perhaps akin to enfeoffed ‘knights’ in medieval Europe.48 The stratification that emerges from the later literary sources is more general and reflects the (post-Sasanian) Avestan concept of social stratification. The priests (asronan) appear at the top of the ladder. They are followed by the military estate (artestaran). The third estate is that of the royal bureaucracy (dibiran, i.e. scribes). Finally, the commoners are enumerated, subdivided into peasants (vastaryoshan) and artisans (hutuxshan). If the two hierarchies, inscriptional and literary, are to be amalgamated, the inscriptional hierarchy of nobility should be seen as an expansion of the second estate in the literary sources; on the other hand, the literary hierarchy may not be contemporaneous, since there is no evidence for a separate priestly caste in the early period. Royal power and influence depended to a large degree on effective control of the shahrdaran, as well as on the active support of the majority of the vuzurgan, or equivalent groups, whatever their names in later periods. Their cooperation would be needed for the recruitment of the asavaran who owed them allegiance, and their consent would be required for the imposition of royal taxation within their domains. Sasanian military organisation has been described as feudal, basically similar to its Arsacid predecessor, and this definition may help us to understand how the Sasanian regime worked. From our meagre information about remuneration for the professional core of soldiery, we may conclude that it was supported through land-grants rather than paid in money or kind. Thus it is tempting to accept the notion of enfeoffment, which by its very nature entails bonds of trust and dependence that may be described as ties of vassalage. Yet, if this picture provides a fairly accurate idea of the relationship between the shah and warriors conscripted in his own domain, as well as of that between the grandees and their own warriors, it does not reveal the realities of the links between shah and grandees. The grandees’ domains might have been deemed fiefs granted by the shah, but in most cases this status would only have been theoretical, since forfeiture of such fiefs to the crown could hardly be enforced by means of a simple legal procedure, without recourse to arms: as in any feudal monarchy, there was no guarantee that every Sasanian shah could control all the grandees all the time. There are clear signs that the great nobles of the Sasanian kingdom developed their own concept of legitimation. It was one of basic loyalty to the royal dynasty, but this by no means entailed unconditional loyalty to the individual seated on the throne at any given moment. The shah in power might be replaced by another member of the dynasty if a significant body of nobles found his reign unjust and tyrannical. The nobles likewise did not consider themselves utterly bound to abide by a reigning shah’s own choice of successor. A more suitable candidate might be substituted for his appointee, provided that he came from among the members of the royal house.