In many ways the Mongol army was similar to its Xiongnu and Turkish
[Turkic] predecessors. It consisted almost exclusively of cavalry: mounted
archers armed with short and long-range arrows, sabers, lances and maces. They
wore steel cap helmets and armor consisting either of lacquered bide or
overlapping iron scales. Organized around decimal units of 10, 100, 1000 the
largest Mongol tactical division was the “Tumen” of 10.000 men. Although the
decimal system had been employed by the Xiongnu, in an imperial confederacy
unit commanders were also tribal chiefs in their own right and so often decided
on their own what orders to accept. The Mongol armies had no autonomous tribal
base so its commanders could expect absolute obedience down the whole chain of
command. Like most nomad armies the total number of Mongol troops was
surprisingly small. At the time of Chinggis Khaan’s death in 1227 it consisted
of only about 138.000 effectives, and even at the height of the empire a
generation later it had about twice that number.
What distinguished the Mongol military from its predecessors, however,
was its iron discipline and central control, a model of organization first
developed by the Manchurian Khitan who had conquered northeastern China three
centuries earlier, but never previously employed in Mongolia. Xiongnu and Turkish
[Turkic] cavalry armies had tended to be disorganized in battle, with each
individual fighting for his own gain. The Mongol army was trained to fight as a
coordinated group following signals from flags or horns. Those individuals who
broke ranks either to advance or retreat, those who engaged in personal combat
without regard to orders, or those who stopped to loot, were severely punished.
Nobody, under pain of death, was allowed to move to another unit without
permission. Because his trusted military commanders were not rivals for
political power, Chinggis Khaan gave them a great deal of autonomy to carry out
his overall strategy. And he was a brilliant talent spotter, for out of the
Mongol ranks rose a series of world-class generals who led his armies to
victory across Eurasia.
But perhaps Chinggis Khaan’s unique innovation was his incorporation of
military engineers, Chinese and later Muslim, into the Mongol army after his
first campaigns in China. These specialists provided the Mongols with thousands
of siege engine that could be used to take fortified cities: catapults for
burling stones ballistae for throwing javelins, and other machines for throwing
fire. They also provided him with the ability to bridge rivers or even divert
them to wash away enemy fortifications. All other steppe cavalry armies had
been stymied by walled cities. They could attack around the, and lay waste to
the countryside but they could not take them by direct assault. Without this
ability, no nomadic group could ever expect to conquer well-defended sedentary
lands. The Mongol army could and did. It became so efficient that none of the
great walled cities of Central Asia were able to withstand their power when
Chinggis Khaan launched his war there against the Khwarazm Khan in 1218.
These innovations gave Chinggis Khaan a military machine that was
completely under his control, that fought according to a coordinated plan, and
that the ability not only to strike deeply into enemy countries but (unlike any
nomads before or since) to engaged in effective siege craft that rendered
walled cities vulnerable to a steppe army. It was an army of conquest, not a
grand raiding force like those of the Huns in Europe or the Xiongnu against
China. And conquer it did.
Professor Thomas J. Barfield, Boston University, excerpted from a longer
text titled “Something New Under the Sun: The Mongol Empire’s Innovations in
Steppe Political Organization and Military Strategy”, prepared for the 8th
International Congress of Mongolists, held in Ulaanbaatar in 2002.
Resource: Carl Robinson "Mongolia Nomad Empire of Eternal Blue Sky"