The direct cause of Genghis Khan’s Western Expedition: Khwarezm Khan’s betrayal of justice. Scholars of Liao, Jin, and Yuan history are familiar with the historical behaviors of the three major tribes of Khitan, Jin, and Mongolia that prospered in northeastern my country during the Middle Ages. The political purpose is to seize the Central Plains and rule China. So in 1219, Genghis Khan had captured the central capital (today's Beijing), and was about to march into Bianjing (today's Kaifeng) in one go. The destruction of the Jin Dynasty was just around the corner. Why did he stop halfway and go all the way to the west? Since ancient times, some Western historians have described Genghis Khan's Western Expeditions as a scourge, but they have been very secretive about the causes of Genghis Khan's Western Expeditions. The basis of historical facts is that Genghis Khan's Western expedition was directly related to the treachery of Mahamo, the great Khan of Khwarezm who was dominant in Central Asia at that time - in 1210, Mahamo defeated Western Liao (the Liao royal family Yelu Dashi established in Xinjiang Country) King Gu came out of Ruke and wanted to continue to expand eastward. In 1215, Mahamo sent an envoy headed by Haradin to China. They met with Genghis Khan near Zhongdu and received generous courtesy. Afterwards, Genghis Khan sent a return mission. In 1218, the envoy arrived in Khwarezm and handed over a letter from Genghis Khan to Mahamo. The main idea of ??the letter was: We now have the responsibility of being friends with our neighbors, and the path of human coordination should be followed by both parties; the responsibility of friendship should be borne; we should There is a duty to support and aid one another in case of misfortune; and to keep the well-traveled and deserted roads open safely, so that merchants may come and go in safety and without restraint. Before the return mission returned to the capital, the Mongolian caravan arrived at the border town of Khwarazm. General Khwarezm, who was guarding the city, was also jealous. He was jealous of the caravan's large amount of property and actually detained the caravan as a spy. After the report was reported, the Great Khan Mahamo ordered all the caravan members to be executed and the property confiscated. Only one camel driver escaped and sent a message to Genghis Khan. Genghis Khan remained calm despite his anger. On the one hand, he sent General Zhebei to pursue and annihilate Guchuluq, the king of Western Liao who was entrenched in Xinjiang, and to detect the movement by throwing stones to ask for directions; on the other hand, he sent an envoy headed by Ibn Hafurazhi Bullah to Khwarazm. Ask Mahamo. Mahamo had no answer, so he killed three more envoys. The Great Khan of Khwarezm, Mahamo, repeatedly provoked Genghis Khan. With no way to retreat, Genghis Khan personally led an army of 200,000 to fight against Khwarezm. When Genghis Khan came to the west, Maha had a guilty conscience, so the only thing he could do was to seek divination from gods and ask for fortune-telling. In fact, Khwarezm has 400,000 elite soldiers, and its territory and territories are very large. It reaches the Syle River in Kazakhstan in the northeast, the Indus River in the southeast, Azerbaijan in the northwest, and the Persian Gulf in the southwest. However, its territory is vast but under-governed, its area is rich but its expropriation is excessive, its people are numerous but massacres are carried out, its soldiers are numerous but its generals are vast, but its orders are numerous. There are two groups of people, the king and the queen, who are worried about the internal affairs of the court, and the nobles who are worried about the external affairs are intrigues and spying on each other. In September 1219, Genghis Khan’s army entered Khwarezm. By March 1220, eight cities including Buhua La were captured in half a year. Then, the three-pronged Mongolian army joined forces and captured Samarkand, the capital of the country, where 110,000 troops were stationed in three days. At the end of 1220, Genghis Khan successively captured more than ten famous cities such as Shabul. From Samalgan to the shore of the Caspian Sea, Mahamo ran in front and the Mongolian army chased behind. Mohamo fled all the way without encountering an enemy. In a small boat, he rowed into a remote island in the Caspian Sea. It was difficult for the Mongolian cavalry to set foot there, but he was safe and sound. However, God did not bless him, God did not work, and despite being frightened, his death was inevitable. Taking advantage of the opportunity of killing a caravan, he was in great misfortune! With his eldest son Zhalandin, Mahamo Khan finally got a good death. On November 20, 1222, Zharendin garrisoned Gejining, an important town in the southeast of Khwarezm. Hearing that Genghis Khan was personally leading an army to attack, he withdrew southward to the Indus River, and was forced to fight again with the pursuing Mongolian army. In a fierce battle, he lost almost all his men and horses, and he jumped into the Indus River alone and died in India. The voices of Mahamo and his son were vague, and Khwarazmo, the khanate across Central Asia, perished from then on. Like most tribes in the ancient East, Mongolia, which had just entered the stage of civilization at the beginning of the thirteenth century, still could not get rid of the political system of feudal land and nation-building. After the war was over, Genghis Khan entrusted his eldest son Shuchi to the Kipchak grassland, and then there was the subsequent conquest. Without antecedents, there would be no consequences, which Mahamo had never thought of.

At the beginning of the 13th century, before Genghis Khan established the Great Mongol Kingdom, Mongolia was still in the patriarchal era. There was a traditional custom in this era that once a family or tribe formed a grudge against someone, they would be enemies for generations. Khwarezm's murder of the Mongolian envoy was a national hatred, so Genghis Khan sent a second mission to ask Mahamo to sincerely repent and provide compensation and compensation to the caravan. He originally wanted to endure the humiliation and bear the burden and not start a war, but what else could he do when Mahamo was on his nose and on his face? We can also get a clue of this from the letter he sent to Mahamo, the first friendly mission.