Beate Dignas & Engelbert Winter - Kaveh Farrokh

126 4 The diplomatic solutions
to conclude the treaty. 32 In Iranian–Roman relations the venue for peace
negotiations was a formal element as important as the accurate diplomatic
ceremonial and was also seen to reflect the political balance of power.
Diocletian’s policy in the East was shaped by an attempt not to overexert
the capacities of the empire, to refrain from expansion and to be content
with a restoration of the borders that had been fixed by the Eastern policy
of the Severi. In spite of Diocletian’s strong position in 298 Rome did not
show any aggressive or universal aspirations; instead, Diocletian intended
to acknowledge the sovereignty of the defeated Sasanian king. This is illustrated
by the place where the foedus of 298 was concluded and which was
accepted, perhaps even chosen by Rome, together with the moderate terms
of the agreement. According to Peter the Patrician Narsē had to give his
consent to three important Roman conditions. The first of these concerned
territory and a clarification of the situation along the Sasanian–Roman and
Sasanian–Armenian borders. 33 Locating the so called ‘provinces beyond the
Tigris’, which had to be ceded to Rome, poses problems (map 8). 34
Peter the Patrician singles out five regions: Ingilēnē and Sōphēnē geographically
comprise the area between the Tigris and the Nymphios. The
third province, Arzanēnē, borders these in a south-eastern direction, also
situated along the upper Tigris and starting from the eastern banks of
the Nymphios. 35 Adjacent to this province are the regions Karduēnē and
Zabdikēnē. A comparison with other sources 36 fleshes out our map of the
area. The area between the Euphrates and the Nymphios and further east
into Karduēnē actually included nine and not five regions.
Moreover, our author’s statement that the Tigris was supposed to be the
new borderline between the two powers seems to contradict the fact that
most areas ceded to Rome were located beyond the Tigris. This is confirmed
by the ancient author Festus, who wrote in the fourth century and
was thus much closer to the events of 298 than Peter the Patrician. Festus
claims that the Romans gained power over five peoples across the Tigris. 37
Ammianus Marcellinus also mentions the regiones Transtigritanae. 38 Differentiating
between a situation de-iure and one de-facto may help to explain
the diverging accounts of Peter the Patrician and Festus. Whereas the latter
describes the official situation which assigns the so called ‘provinces beyond
the Tigris’ to Rome, the Byzantine historian describes the real situation that
was created by an administrative practice in these provinces soon after 298. 39
32 Winter 1994: 603–5. 33 Winter 1989b: 555–71. 34 Adontz 1970: 25–37.
35 On this province see also Whitby 1983: 205–18.
36 Amm. xxv.7.9. 37 Fest. 14.25. 38 Amm. xxv.7.9.
39 Dillemann 1962: 217–18; see also Felix 1985: 125–6.