s were not greatly at a
disadvantage; and cavalry alone cannot gain, or even save a battle.
When Darius put himself into a position where he lost all the advantages
derivable from superiority of numbers, he made his own defeat and his
adversary's triumph certain.

It remained, therefore, before the Empire could be considered as
entirely lost, that this error should be corrected, this false step
retrieved. All hope for Persia was not gone, so long as her full force
had not been met and defeated in a fair and open field. When Darius fled
from Issus, it was not simply to preserve for a few months longer his
own wretched life; it was to make an effort to redeem the past--to give
his country that last chance of maintaining her independence which she
had a right to claim at his hands--to try what the award of battle
would be under the circumstances which he had fair grounds for
regarding as the most favorable possible to his own side and the most
disadvantageous to his adversary. Before the heart of the Empire
could be reached from the West, the wide Mesopotamian plain had to be
traversed--there, in those vast flats, across which the enemy must come,
a position might be chosen where there would be room for the largest
numbers that even his enormous Empire could furnish--where cavalry and
even chariots would be everywhere free to act--where consequently he
might engage the puny force of his antagonist to the greatest advantage,
outflank it, envelop it, and perhaps destroy it. Darius would have
been inexcusable had he given up the contest without trying this last
chance--the chance of a battle in the open field with the full collected
force of Persia.

His adversary gave him ample time to prepare for this final struggle.
The battle of Issus was fought in November, B.C. 333. It was not till
the summer of B.C. 331, twenty months later that the Macedonian forces
were set in motion towards the interior of the Empire. More than a year
and a half was consumed in the reduction of Phoenicia, the siege of
Gaza, and the occupation of Egypt. Alexander, apparently, was confident
of defeating Darius in a pitched battle, whenever and under whatever
circumstances they should again meet; and regarded as the only
serious dangers which threatened him, a possible interruption of his
communications with Greece, and the employment of Persian gold and
Persian naval force in the raising of troubles on the European side of
the Egean. He was therefor