Islam • 31in their new empire had become dhimmis (protected subjects),
they could not be raided or attacked in any way. It had always
been a point of honour among Arabs to treat their clients
well, to come to their aid, or to avenge an injury done to them.
Dhimmis paid a poll tax in return for military protection, and
were permitted to practise their own faith, as the Quran en-
joined. Indeed some of the Roman Christians, who had been
persecuted by the Greek Orthodox for their heretical opin-
ions, greatly preferred Muslim to Byzantine rule.
Umar was determined to maintain good discipline. The
Arab soldiers were not to enjoy the fruits of victory; the con-
quered lands were not to be divided among the generals, but
left to the existing cultivators, who paid rent to the Muslim
state. Muslims were not allowed to settle in the cities. Instead,
new "garrison towns" (amsar) were built for them at strategic
locations: Kufah in Iraq, Basrah in Iraq, Qum in Iran, and
Fustat at the head of the Nile. Damascus was the only old city
to become a Muslim centre. A mosque was built in each of the
amsar where the Muslim troops attended Friday prayers. In
these garrison towns, the soldiers were taught to live an Is-
lamic life. Umar stressed the importance of family values, was
hard on drunkenness, and promoted the ascetic virtues of the
Prophet, who, like the caliph himself, had always lived frugally.
But the garrison towns were also Arab enclaves, where those
traditions that could be accommodated with the Quranic
world-view were continued on foreign soil. At this point,
Islam was an essentially Arab religion. Any dhimmi who did
convert had to become a "client" of one of the tribes and be
absorbed into the Arab system.
But this period of triumph came to an abrupt end in
November 644, when Umar was stabbed in the mosque of
Medina by a Persian prisoner-of-war who had a personal
grievance against him. The last years of the rashidun were
characterized by violence. Uthman ibn Affan was elected as