THE MEDITERRANEAN WORLD IN LATE ANTIQUITYthe context of the assassination of Muhammad’s cousin and son-in-law ‘Ali;
this was followed by the death of the latter’s son, Muhammad’s grandson,
Husayn, at Karbala in 680.^38 The murder of ‘Uthman in particular (656) gave
the Byzantines a breathing space and the chance to reorganize, but Heraclius
had already begun the process of changing the army structure, and there was
also work on the refortification of key coastal cities in Asia Minor.^39
It is naturally tempting to imagine that after decades of warfare the
Byzantines were in no condition to take on another enemy, but less easy to
assess the actual military strength of the empire in the east; to the arguments
that there had been a progressive reduction in defence and that Heraclius’s
campaign against the Persians in the 620s was only possible because of des-
perate recruiting measures, it may be responded that Byzantium was still capa-
ble of gathering and dispatching considerable forces both before and after the
Arab conquests.^40 The contest was not all one-sided and the Muslims suffered
several serious reverses. The late seventh and early eighth centuries were very
difficult for the eastern empire, and there is also a gap in the coverage of the
historical sources for about twenty years in the mid-seventh century, so that
much detail remains obscure; one can imagine, however, that a serious less-
ening of the availability of elite education followed the loss of territory and
the damage to cities. The state had lost a huge part of its tax-base and in the
capital the Aqueduct of Valens which was essential for the city’s water sup-
ply was not repaired after being damaged during the 626 siege, with a conse-
quent dramatic downward impact on the population. The Emperor Constans
II (641–68) moved his court to Sicily and was eventually assassinated. The
Mediterranean became unsafe and open to the development of Arab piracy.
But above all, Constantinople was not taken. The Byzantine state was much
reduced and had to change its administrative, financial and military structures
as a consequence. But its core institutions were able to adapt and survive.^41
This was so despite the strength of the opposition, especially from the
eastern provinces, to the efforts of Heraclius earlier in the century to find
a solution to the christological divisions which still separated the church
(Chapter 8). Miaphysites were not the only anti-Chalcedonians; the so-called
‘Nestorians’ also maintained that Christ had only one nature (the human),
and the decisions of the Council of 553 had met with hostility in Italy. The
successors of Justinian did not give up on their efforts to manage the situ-
ation, which was seen not only as politically dangerous but also as likely to
bring divine punishment on the empire. The first formula was promoted by
Heraclius in 633, soon after his success in restoring the Cross to Jerusalem, but
Monoenergism, the theory that Christ had one ‘energy’, provoked opposition
from Chalcedonians, and in 638 an imperial statement, the Ekthesis, displayed
in St Sophia, proclaimed Monotheletism, the theory that Christ had a single
will.^42 In the same year Sophronius, as patriarch of Jerusalem, surrendered
the holy city to the Muslims, but he had already been a leader in orchestrat-
ing local meetings of bishops to oppose the innovation, and formally con-
demned the imperial religious policy.^43 Sophronius died, also in 638, and the