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A S T R A T E G I C GEOGRAPHY
Byzantium was both the beneficiary and the prisoner of its geography. The eastern
empire of Late Antiquity saw out the crises that overwhelmed the western empire
in the fifth century in part because the Balkans gave protection from Goths and
Huns, and the position of Constantinople at the eastern extremity of the Thracian
peninsula made it possible to construct effective landward defences and to supply
the city by sea (Heather 2005: 167-90). The fragmented nature of Balkan relief
made the peninsula hard to control as a single unit, and does much to explain
how politically primitive Slav tribes managed to establish themselves throughout
the peninsula in the sixth and seventh centuries. At the same time though, Balkan
geography militated against the establishment of a single threatening power as a
neighbour to Byzantium. The Huns in the fifth century, the Avars in the sixth
century, and the Magyars in the tenth century all established themselves on the
Hungarian plains from where the routes to Constantinople available to a nomad
army are limited in number and easily blocked. The Bulgars established themselves
on the plains south of the Danube, closer to Constantinople and protected from
Byzantine counter-attack by the line of the Haimos mountains, but this is no
country to support a nomad power in the long term. If historians have argued
that no nomad great power could maintain itself on the Hungarian plains due to
inadequate supplies of pasture, the same is much more true of any nomad power on
the lower Danube. By the tenth century, if not long before, the Bulgars had ceased
to be a steppe nomad culture (Whittow 1996: 262-98).
Similarly the empire of the seventh century survived because the capital and
the agricultural resources necessary to feed it, at least at a reduced level, were
protected from the centres of Persian and Arab power. An army planning to reach
Constantinople from Syria will have to travel over 1200 kilometres, cross two mountain
ranges and a plateau where water and food will have to be transported. As
the Franks discovered in 1097 and again in 1101 this was not an easy journey, and
the tenth-century military manual known as De velitatione bellica ('Skirmishing
Warfare') shows how adeptly the Byzantines had learnt to exploit the defensive
possibilities of the terrain (see III.18.8 Military texts).
Through the eighth and ninth centuries Anatolia was most exposed to raids
coming from the east, in which direction the mountains do not form a barrier.
The loss of Armenia in the seventh century in effect turned the Byzantine defences,
and the eighth-century establishment of the Arabs at Melitene (Eski Malatya) and
Kalikala (Erzurum) gave them convenient raiding bases on the plateau. The fall
of these two cities to the Byzantines in 934 and 949 respectively was a decisive
stage in the empire's tenth-century eastern offensive. In both cases the specific local
geography is an important key to what happened. The two cities lay in the middle of
relatively fertile alluvial basins surrounded by mountains. As long as the mountain
population was friendly the cities were secure; when they turned to alliance with
the empire Melitene and Kalikala were doomed (Whittow 1996:315-18,322).
Anatolian geography also does a great deal to explain the history of the eleventhand
twelfth-century empire. The Turkish threat that faced Byzantium came from
the open east flank of the peninsula rather than its protected south-east—hence
Romanos IV's fatal confrontation with the Seljuk sultan which took place at
Manzikert in the Armenian Transcaucasus. Defeat there opened the way to the
plateau, where Turkoman nomads from Central Asia found a relatively familiar
environment to exploit. Hendy.(i97o) pointed out to a generation prone to think of
central Anatolia as the empire's heartland that the peninsula's richest areas actually
lay on the coast and were still Byzantine through the greater part of the Komnenian
period. One might question whether the coastlands were viable if the plateau was
in hostile hands, but otherwise Hendy's observation remains true.
The empire was so concerned with the defence of Anatolia because of the disaster
that had overwhelmed its eastern provinces in the seventh century. At a stroke the
loss of Egypt reduced Byzantine status to that of a second-rank power. Neither
Anatolia nor the Balkans (where in any case, other than for a period between
the early eleventh and late twelfth centuries, imperial control was shared with
regional rivals) could compensate. Still less could the territories in the central and
western Mediterranean, unless of course the decision had been taken to move the
capital from Constantinople to somewhere much further west. The seventh-century
crisis was in turn shaped fundamentally by the peculiar geography of the Levant
and the adjacent desert. Islam grew up in the isolation of Arabia. Close enough
to be influenced by Judaism and Christianity; far enough away for the tribes of
deep Arabia not to have become Christian. The conquests in turn are explained
by the openness of the heartlands of the Fertile Crescent to an invader from the
desert and the difficulty of finding a new defensive frontier south of the Taurus
mountains.
An empire confined to Anatolia and the Balkans could prosper (as Byzantium
did in the tenth and eleventh centuries, or as the Ottoman Empire did between
the mid-fourteenth and early sixteenth centuries) but the resources of these regions
were insufficient for more than regional dominance. The loss of Egypt marks the
end of a Byzantine golden age; its conquest in 1517 opened the way for its Ottoman
equivalent.