All the healthy males among the Mongols carried arms. In times of need, they served as an army. In short, the Mongolian army was small and uni-tribal. But with the unification of the different Mongolian tribes and with the wars with different peoples, there were changes in the nature and structure of Genghis Khan’s army. The army became big and multi-tribal. In the army, there were soldiers who accepted the authority of Genghis Khan willingly, like the Turkic Uyghurs and defeated the people like the Keraits. Genghis Khan unified the different tribes of Mongols and made them into a confederacy. He tried to destroy the earlier tribal identities of these tribes.

Genghis Khan organized his army on a decimal basis. The units were in multiples of 10. (10,100, 1000,10000, etc.) 

The greatest contribution of Genghis Khan was the courier system called Yam he introduced. This Yam system was a relay system that linked different administrative units of his vast empire. At xed distances, there were horsemen and messengers for carrying messages. To maintain this communication system, the nomadic Mongols had to give one-tenth of their animals (horses or other animals) to the authorities. This was known as Qubkar (kar means tax-likeour’karam’inMalayalam). 

After the death of Genghis Khan, the courier system became more efficient. Its speed and reliance had surprised visitors. The great Khans used this relay system to effectively control their far-flung regions. The defeated people were not happy with the new nomadic rulers. After the attacks that took place in the first half of the 13th century, cities were destroyed, farms were left uncultivated and trade and handloom industries were reduced. 

Thousands of people were. killed and many more were made prisoners. Right from the top to the bottom, people suffered different kinds of misery and pain. Since the canals in the internal region of the Iranian plateau were not repaired, the desert expanded. This caused environmental min. A good portion of the Khurasan Region never. recovered from this damage. 

Once the attacks were over Europe and China were regionally connected. The trade relations between the two were also better. The trade and travel through the silk route reached their height under the Mongols, But the trade routes did not end with China. They extended to Mongolia, the heart of the Empire and Karakoram. Travel and communication were essential for the stability of the Mongol rule. The travelers were given a pass for their easy travel. Merchants had to give a tax (called Baj tax) for this. 

In the 13^th century, the contradictions that existed between the nomads and the permanent settlers began to lessen.

The memories of Genghis Khan were cherished by his successors. It was his Yassa (Law) that helped him to be remembered by posterity. In the Assembly of Chiefs (Quriltai) in 1206 Genghis Khan declared his Yassa. It contained administrative controls and laws regarding the organization of hunting, army and postal system. By the middle of the 13 century, the Mongols began to use the word Yassa to mean the “Laws of Genghis Khan”. Thus the Yassa of Genghis Khan helped him in keeping memory alive.