104 | CHAPTER 4
and Asia Minor, the Aegean, and the Balkans to the North. These three re-
gions (the last variously extended westward, as noted above) constitute a vast
triptych at the meeting of Asia and Europe.
I shall call this triptych of regions the “Eurasian Hinge.” It displays some
striking geographical features that define and articulate it (see further below).
But we should be wary of positing serious geographical and even geopolitical
lines of division or noncommunication. Iran and Iraq interact despite the
Zagros Mountains between them; indeed Iraq was the Sasanian Empire’s
urban heartland.^46 Greater Syria communicates by land and sea with Eg ypt, a
country so distinctive that neither “Mediterranean” nor “Middle Eastern”
nor “African” does it justice.^47 Its role as granary for the ancient Mediterra-
nean and Middle East derived from the Nile flood created by the East Afri-
can monsoon regime over Ethiopia, independently of Mediterranean—but
not Indian Ocean—climatic vagaries.^48 Again, the Persian Gulf is linked to
the Mediterranean via the Tigris- Euphrates route: the Syrian desert is not
really “a clear geographical divide,” nor the Euphrates a “geographically im-
perative” frontier or “fatal limit”.^49 Outsiders (and even Eusebius of Cae-
sarea) may have seen things that way, and Euphrates or Tigris frontiers have
even acquired considerable symbolic force.^50 But they have actually repre-
sented nothing more profound than a political and military stalemate, the
inability or indisposition of the powers on either side—the Sasanians and
Romans, who claimed to be “the world’s two eyes,”^51 are the clearest in-
stance—to eliminate the other and so realize the Fertile Crescent’s inherent
46 W. Eilers, “Iran and Mesopotamia,” in E. yarshater (ed.), The Cambridge history of Iran 3(1)
(Cambridge 1983) 481–504; Pourshariati, Decline and fall [1:22] 38–41.
47 R. Bagnall, “Eg ypt and the concept of the Mediterranean,” in Harris (ed.), Rethinking the Medi-
terranean [3:109] 339–47.
48 R. Ellenblum, The collapse of the Eastern Mediterranean (Cambridge 2012) 24.
49 See respectively J. Haldon, “Framing transformation, transforming the framework,” Millennium
5 (2008) 348–50; E. Frézouls, “Les fluctuations de la frontière orientale de l’empire romain,” in La géog-
raphie administrative et politique d’Alexandre à Mahomet (Leiden 1981) 225; Gibbon 46: 2.880. M. Som-
mer, “Difference, diversity, diaspora: Locating the Middle Euphrates on imperial maps,” Mediterraneo
antico 9 (2006) 426–27, sees the Euphrates as a social, cultural, and economic frontier, but not as a geo-
graphical divide. Navigation on it was particularly easy when it still ran through forests full of timber for
boatbuilding : Dio Cassius [ed. U. P. Boissevain (Berlin 1895–1931); tr. E. Cary (London 1914–27)]
76.9.3. It can also be thought of as the main artery between the Persian Gulf and the Mediterranean.
Compare C. Noelle- Karimi, “Khurasan and its limits,” in M. Ritter and others (eds), Iran und iranisch
geprägte Kulturen (Wiesbaden 2008) 9–12, on the Oxus as boundary but not barrier.
50 Sommer, Mediterraneo antico 9 (2006) [4:49] 427; Borrut, Entre mémoire et pouvoir [3:79]
207–8, 227, 348.
51 G. Schmalzbauer, “Überlegungen zur Idee der Oikumene in Byzanz,” in W. Hörandner and oth-
ers (eds), Wiener Byzantinistik und Neogräzistik (Vienna 2004) 408–19; Michael Whitby, “Byzantine
diplomacy,” in P. de Souza and J. France (eds), War and peace in ancient and medieval history (Cambridge
2008) 127–29; Canepa, Two eyes of the earth [2:70] 123–25; cf. L. Mecella and U. Roberto, “ ʾIσοτιμία”,
Studi ellenistici 27 (2013) 99–119.