30 ISLAM AT WAR
and sand at their back, more able in these circumstances to fight as indi-
vidual warriors than their enemies were in their formed ranks. The battle
is said to have gone on for six days, which seems a long time for men to
fight with muscle-powered weapons. We do know the Muslims were com-
pletely victorious, and nothing remained to stop them from snapping up
the entirety of the Palestinian and Syrian provinces.
Although Yarmouk is little known today, it is one of the most decisive
battles in human history. With this victory, Islam became the dominant
religion in all of the modern Middle East. Palestine and Syria became
Muslim nations. The road to Egypt was opened, and through Egypt and
Syria, Muslim caliphs acquired the naval force to spread the religion and
their power throughout the southern Mediterranean basin, all the way to
Spain. Had Heraclius’s forces prevailed, the modern world could be so
changed as to be unrecognizable. The governments and people of Syria,
Jordan, Israel, and Egypt would be most unlike what they are today.
The conquests of Syria and Persia completely absorbed the energy of
the Caliph Umar’s new state for a time. Two astonishing and overlapping
campaigns had drained the Arabian Peninsula of manpower. Even after
the conquests were well in hand, there were garrisons to be held, field
armies to be maintained, and an administration to be built for the new
empire. The strategic situation of the caliphs was generally favorable.
Persia was no threat, Byzantium was in sharp decline, and no other ene-
mies had appeared. If warriors were in short supply, gold was not. It had
become the standard practice of the invading Arab armies to send a tithe
of their loot to Medina. The Muslim state was rich. In the seventh century
wealth could buy warriors and could pay for the maintenance of those
already in service. The conquered peoples were not slow to accept the
new religion and the military service that went with it. Leaders too were
available, and few states have been as fortunate in the loyalty and skill of
their generals as the early Arab Empire. It is interesting that the loyalty
and devotion shown by Khalid, the greatest of the Arab generals, was not
repaid by the caliph. Like any successful warrior of the time, Khalid had
taken his share of the vast loot won by the armies that he commanded.
He became immensely wealthy, and although his honor was never in ques-
tion, he was not a devout man. Caliph Umar, however, required devotion.
Two years after Yarmouk, Khalid was dismissed in disgrace and never
served again. It is fortunate for the new empire that no great foreign
challenges emerged at this time.
The Caliph Umar probably authorized some action against Egypt in
639 when he was visiting Jerusalem. Amr ibn al Aasi was permitted to
make an attempt with a smallish army traveling along the Mediterranean