"كتيّب سوريا (بما في ذلك فلسطين). لندن: إدارة استخبارات الأركان البحرية، يونيو ١٩١٩" [ظ‎‎٦‎٧] (٧٣٨/١٣٩)

128
MILITARY HISTORY
that the Arabs won their victories as an army of horsemen.
On the contrary, most of them fought on foot and they became
famous horsemen only after they had conquered the horse-
breeding lands of Syria and Persia. The view that they
owed their success to their enormous numbers does not bear
critical examination. In reality 5,000-6,000 was a great force
even for the united Arab tribes to assemble. The Moslem
invasion of Egypt in 639 was begun by an army of 4,000 men.
The latest historian of the period gives 20,000-24,000 as the
maximum strength of the Moslems at the battle of the
Yarmuk and regards 10,000 as a more probable estimate.
In any case the Greek army was not much, if at all, inferior
to the invaders in point of numbers. Finally, the part played
by the new faith of the Arabs has probably been overstated
and has perhaps been wrongly conceived. The popular view,
supported by Moslem tradition, that the Arabs set out to
conquer the world for their faith can hardly be maintained.
The influence of Islam consisted rather in this that the Arab
tribes for the first time acted together in virtue of their
common faith, and that a common direction and purpose were
secured for their enterprises by the authority of the Khalifs,
the successors of Mohammed. It was only later, perhaps,
that Islam supplied such a sense of confidence and superiority
as to become an appreciable source of military strength.
It remains to be said that even in the battle of the Yarmuk
the Arab army seems to have been arranged according to
a definite tactical plan. The front lines consisted of infantry
and the cavalry was posted in the rear in support, especially
on the flanks. There was probably a reserve under the chief
commander, Abu ‘Ubeidah. The disposition and tactics of
Moslem armies from now onwards were plainly influenced by
Greek and Persian models. Possibly Greek military principles
influenced to some extent even the leaders of the conquest.
The final result of this development is plainly seen in the
period of the Crusades and will be described under that period.