October 1, 2026: Sometime around 1160 AD, a Mongol chieftain named Yesugei saw his first son, Temugin, born. After working with powerful tribal leaders named Jamukha and Toghrul. The trio built a powerful alliance on their portion of the Great Eurasian Steppe. Eventually, the triumvirate fell apart with Temujin defeated in 1187 and seeking refuge, as many Mongol leaders did, with the Chinese Jin dynasty. Nine years later, Temujin returned, defeated his enemies, and by 1206 ruled the Mongolian steppe. Temujin also renamed himself Genghis Khan and began reforming the Mongol tribes, introducing well-thought-out unit structures for his army and creating a meritocracy out of the many competing Mongol leaders. That meant if you followed orders and won, you could be promoted. If not, you could keep trying until you succeeded or failed and were cast aside.

Another major obstacle was the Chinese Jin Dynasty and the interference they brought to Mongolian military and political affairs. The Jin dynasty also descended from Manchurian tribes and regularly interfered with steppe battles and politics. The Great Jin dynasty lasted 115 years, until 1234. While they began as nomads, they eventually became like the Chinese they ruled. The Jin Dynasty ruled northeastern China, Manchuria, and portions of Siberia.

The Jin pitted their tributary tribes, such as the Mongols and Tatars, against one another to divide and rule them. The Jin initially supported the weaker Mongols against the Tatars, but when the Mongols grew stronger, the Jin switched sides in 1161. Nonetheless, Jin support had given the Mongols the boost they needed to organize and arm their warriors.

As Genghis Khan began his conquests, the Jin were intimidated to the point where they agreed to become an ally and persuade others to do likewise. Genghis also went after the Tatars, who had poisoned his father. Together, the Mongols and Jin crushed the Tatars in 1196, and the Mongols absorbed them. The Mongols later attacked and brought down the Jin Dynasty in 1234.

Genghis's great conquests would not have been possible without motivating the hundreds of thousands of young men who followed him. Genghis assured his followers that they would not only become wealthy but also gain sexual access to all the conquered women. As nomads, the Mongols had relatively few luxuries or material goods. Now, as conquerors, they had access to all the comforts of a settled society. Conquered cities were rebuilt to accommodate the Mongol conquerors, and Mongols enjoyed the relatively luxurious life of city dwellers. Some Mongol soldiers settled in conquered cities as garrisons. To keep his army going, Genghis conquered and absorbed neighboring nomadic armies. To keep all this functioning, Genghis had to keep conquering more territory and cities. The conquered cities remained centers of commerce and industry, run by people the Mongols had enslaved. If the conquered people cooperated, they prospered; if not, Genghis returned, destroyed the city, and enslaved the survivors. This did not happen often, as word soon spread through the known world of what happened to those who opposed Genghis.

Genghis was content with his East Asian empire until his forces encountered Shah Ala ad-Din Muhammad, ruler of the Khwarezmid Empire in what is now Iran, Turkmenistan, Uzbekistan, and Kyrgyzstan. Initially, Genghis Khan sought peace and trade with the Khwarezmian shah, telling them he was the master of the lands of the rising sun, while he ruled those of the setting sun. Let us forge a treaty of friendship and peace. Shah Muhammad accepted this treaty, but when a Mongol trade caravan arrived in the Khwarezmian city of Otrar in 1219, the Mongol traders were massacred, and their goods were stolen.

An angry Genghis Khan sent diplomats to Shah Muhammad to demand restitution for the caravan. Shah Muhammad responded by beheading the Mongol diplomats and sending the heads back to Genghis. This proved to be an epic error in judgment. By 1221, Genghis and his armies had killed Shah Muhammad, chased his son into Indian exile, and destroyed the vast Khwarezmid Empire.

When Genghis died in 1227, his four sons had already been assigned to lead armies in different directions to avoid a Mongolian civil war. Jochi went north and founded the Golden Horde that would rule Russia. Tolui turned south and sacked Baghdad, the seat of the Abbasid Caliphate. Genghis Khan appointed his third son, Ogodei, as his successor and ruler of the Mongol homelands. Chagatai was left to rule over Central Asia, consolidating the Mongol victory over Khwarezmid lands. Meanwhile, back in Mongolia, the situation was rather more dismal. With most of the men now settled in their conquered territories, the women, children, and elderly left behind lived in relative poverty. But at least they did not have to fear invasion, for Genghis had eliminated or subdued them all. The Mongols in Mongolia returned to being what Mongols had been for centuries: hunters, herders, and traders.