Timujin, born in the year 1162 into a Mongol tribe, had to struggle in his early years to retain the leadership of his clan. By the year 1206, he had succeeded in unifying the Mongol tribes and had taken the title Genghiz Khan. Successful raids into northern China followed and the northern Chin Empire was brought under his sway by the year 1215. From the Chinese, Genghiz acquired the latest technology of the day in tunnel engineering, siege engines, defensive silk armor and most important, gunpowder.

Relations between Genghiz Khan and Alauddin were at first friendly, although skirmishes had taken place in Sinkiang between the forces of the two empires over succession issues of the local princes. However, a fateful turn of events took place in 1218. Genghiz bought stock in the goods of three Khiva merchants and with them sent Mongol representatives to obtain Khorasani products. Nasiruddin, the governor of the frontier province Otrar, suspected that the Mongols were spies and asked the permission of Alauddin to execute them. The permission was granted and the merchants were slain. Furious, Genghiz sent an ambassador to Nasiruddin and demanded retribution. With the haughtiness and self-delusion that has so often characterized Muslim interfaces with other civilizations, Nasiruddin put the envoy to death. This was an insult that Genghiz Khan could not tolerate. The drums of war were beaten.

Genghiz gathered the Mongol tribes and preparations for war began. Great conquerors pay as much attention to the detailed preparations for war as to the strategies of war itself. Men, horses and supplies were carefully planned and the great mountains of Central Asia were successfully crossed in the winter of 1218-1219. Genghiz was a general par excellence. The first skirmish between Alauddin and the Mongols took place at Otrar on the Amu Darya. The outcome was indecisive. But the Sultan, in his characteristic haughtiness, declared victory, distributed presents to his troops and retired towards Samarqand.

It was at this historic moment that Alauddin Muhammed made a strategic military blunder. He divided up his armies into two main columns and sent smaller contingents to fortify the cities in the Farghana Valley. He thought that the Mongols would withdraw after looting border areas and thus chose a defensive strategy to protect his cities. This gave Genghiz the initiative to focus overwhelming military power at any given geographical point without the risk of facing the full might of the Shah’s forces.

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