Conquerors who unite the steppe usually find that their creation dies with them. Chinggis Khan seems to have understood this danger. Between 1206 and his death he reorganized Mongol society so thoroughly that his empire kept growing for half a century after he was gone. His tools were simple: counting, oaths, writing and a relentless preference for loyalty over birth.

Counting by tens

Chinggis organized his people on a decimal system. Ten warriors formed an arban, ten arbans a unit of a hundred, ten hundreds a unit of a thousand, and ten thousands a tumen, a unit of ten thousand. Steppe peoples had used decimal units before, but Chinggis did something more radical with them. Many units of a thousand were built by mixing men from different tribes, which was meant to weaken old tribal loyalties. A Tatar or Kereyid who once answered to his own chief now answered to a commander appointed by the khan. Men could not leave their assigned unit without permission, on pain of death. Families went with the units, so the army was also a framework for governing the whole population.

The guard and the generals

At the center stood the keshig, the khan's personal bodyguard, which grew to about 10,000 men. It guarded his tent day and night, managed his household and served as a training school. Sons of commanders were required to serve in it, which gave them experience at court and also made them hostages for their fathers' good behavior. Officers of the guard outranked ordinary commanders of a thousand.

Chinggis promoted people for performance. Two of his greatest generals show how far a talented outsider could rise. Jebe, whose name means "arrow," was an enemy archer who, the story goes, wounded Chinggis or his horse during a battle, then confessed and was spared for his honesty. Subutai, a blacksmith's son, became perhaps the most successful general of the century, directing campaigns from China to Hungary. Chinggis's own sons received great armies, but so did men of humble birth who had proven themselves.

Law and writing

Chinggis issued decrees that later writers called the Yasa, covering military discipline, hunting rules, theft and treason. Whether the Yasa was ever a single written code is debated: no complete text survives, and the lists that circulated later may mix real orders with legend. Juvaini and Rashid al-Din both describe the Yasa with admiration, but they wrote decades later, when it had become a symbol of the ruling family's legitimacy as much as a body of rules. What is clear is that the khan's commands bound everyone, including his own family, and that judges enforced them.

To keep records, Chinggis needed writing. After defeating the Naimans, the Mongols captured a Uyghur scribe named Tata-tonga who had served the Naiman ruler, and Chinggis had him teach his sons. The Mongols thereby adopted the Uyghur script to write their own language; a descendant of it is still used in Inner Mongolia and, increasingly, in Mongolia. Chinggis named his adopted brother Shigi Qutuqu as chief judge and ordered him to keep a register, in "blue books," of legal decisions and of how people and pastures were distributed.

Faith, roads and passports

Chinggis himself honored Tengri, the Eternal Blue Sky, and consulted shamans. But he exempted clergy of many religions from taxes and labor, provided they prayed for the khan. Buddhist monks, Daoist masters, Muslim scholars and Christian priests all benefited. The policy was practical as well as tolerant: religious leaders could bless the regime and keep their communities calm. It also had limits. When a powerful shaman, Teb Tenggeri, challenged the khan's authority, Chinggis had him killed.

Communications held the system together. Under Chinggis and especially his son Ogedei, the Mongols built the yam, a network of relay stations with horses placed at intervals along major routes. Official messengers could cover great distances in days, and the stations also housed envoys and merchants traveling on the khan's business. Travelers carried a paiza, a tablet of wood, silver or gold inscribed with the khan's authority, which entitled them to horses, food and protection. In effect it was an early passport and travel warrant.

Worked example: a herder's son in 1210

Picture a young man from a defeated Merkit clan in 1210. Before Chinggis, his status would have depended on his clan, and his clan was now ruined. Under the new order he is assigned to a unit of ten that belongs to a unit of a thousand under a commander who may be a Mongol, a Kereyid or a former slave. If he fights well he may rise to lead ten men, then a hundred. If he deserts, his whole unit may be punished; the friar Carpini later reported that the rest of a unit of ten could be executed if some of its men fled. His family's pastures are recorded in the judge's register. His religion, if he has adopted Nestorian Christianity, is left alone. The system that offers him advancement also watches him closely, and it demands total obedience. That double face, opportunity and control, is a key to understanding Mongol power.