22	A Short History of the Middle East
Northern and Southern Arabia respectively; and the Khawarij
overran Iraq, Southern Persia, and the greater part of Arabia. As a
contemporary poet sang:
'They are split in sects: each province hath its own
Commander of the Faithful, each its throne. . . .'
Thus the Arab nation was torn asunder by the old tribal preten-
sions which Mohammed sought to abolish. That they ultimately
proved fatal to the Umayyads is no matter for surprise; the sorely-
pressed dynasty was already tottering, its enemies were at its gates.
But by good fortune it produced in this crisis an exceptionally able
and vigorous ruler, 'Abd ul-Malik (685-705), who not only saved
his house from destruction, but re-established its supremacy and
gave the Muslim civilization an opportunity to enrich itself cul-
turally. His iron-handed governor of Iraq ruthlessly put down the
rebellion in the eastern provinces, and for twenty years provided
peace and security by his despotic rule. In order to knit together
the far-flung empire and curb the separatist tendencies of the
provinces Abd ul-Malik borrowed from earlier empires the
institution of an official postal system by means of relays of horses;
he substituted for the Byzantine and Persian coins, which had
hitherto been in general use, new gold and silver pieces on which
he caused sentences from the Qur'an to be engraved; and he made
Arabic, instead of Greek or Persian, the official language of
financial administration.1
This reform does not mean that the non-Arab personnel of the
administration, largely Christian by religion in the Levantine
provinces, were replaced. But by this time the social barrier which
'Umar had attempted to impose between the Arab garrisons and
the non-Arab and non-Muslim majority of the population was
beginning to break down. The Arab cantonments had soon grown
into towns and cities; Arabs had acquired land; and, as formerly
between Alexander's Greeks and Orientals, social contact and
intermarriage (for Muslims were permitted to take non-Muslim
wives) were doing their levelling work. Moreover, non-Muslims
1 Nicholson, op. cit., 199 ff. It is of interest that, because these coins bore
quotations from the Qur'an, the eighth-century founder of one of the four
schools of Muslim jurisprudence objected to their being given in payment
to non-Muslims. (D. S. Margoliouth, The Early Development of Moham-
medanism, 119.)