was as venerable as the Roman Empire—and as ambitious. (See Map 1.5 on pp. 30–
31.) King Chosroes II (r.590–628), not unlike Justinian a half-century before him,
dreamed of recreating past glories. In his case the inspiration was the ancient empire
of Xerxes and Darius, which had sprawled from a lick of land just west of Libya to a
great swathe of territory ending near the Indus River. Taking advantage of a dispute
between two claimants to the imperial throne, Chosroes marched into Byzantine
territory in 607. By 613 he had taken Damascus, by 614 Jerusalem. The whole of
Egypt fell to the Persians in 619. But Emperor Heraclius (r.610–641) rallied his
troops and turned triumph into defeat; all territories taken by the Persians were back
in Byzantine hands by 630. (For Heraclius and his successors, see the list on p. 337:
Byzantine Emperors.) On a map it would seem that nothing much had happened; in
fact, the cities fought over were depopulated and ruined, and both Sasanid and
Byzantine troops and revenues were exhausted.
Meanwhile, the Byzantines had to contend with Slavs and other groups north of
the Danube. Map 1.5 on pp. 30–31 makes the situation clear: Slavs—farmers and
stock-breeders in the main—were pushing into the Balkans, sometimes accompanied
by Avars, multi-ethnic horseback warriors and pastoralists. In 626, just before
Heraclius wheeled around and bested the Persians on his frontiers, he was confronted
with Avars and their Sasanid allies besieging—unsuccessfully, as it turned out—the
very walls of Constantinople. It took another half-century for the Bulgars, a Turkic-
speaking nomadic group, to become a threat, but in the 670s they began moving into
what is today Bulgaria, defeating the Byzantine army in 680 and again in 681. By
700 very little of the Balkan Peninsula was Byzantine. (See Map 2.1.) The place
where once the two halves of the Roman Empire had met (see Map 1.1 on pp. 2–3)
was now a wedge that separated East from West.
An even more dramatic obliteration of the old geography took place when attacks
by Arab Muslims in the century after 630 ended in the conquest of Sasanid Persia
and the further shrinking of Byzantium. We shall soon see how and why the Arabs
poured out of Arabia. But first we need to know what the shrunken Byzantium was
like.
Decline of Urban Centers