After the founding of People's Republic of China (PRC), Genghis Khan began to wage predatory wars against neighboring countries. 1205, 1207 and 1209 invaded Xixia three times, forcing Xia Guo to pay tribute. Xixia surrendered and then attacked the rulers with all his strength. 12l 1 year, Genghis Khan invaded the roadside wall in northwest Shanxi, took Changzhou (now Jiuliancheng Scenic Resort Scenic Area in Taibus Banner, Inner Mongolia), Zhou Huan (now the northern suburb of Zhenglan Banner, Inner Mongolia), Fuzhou (now Zhangbei, Hebei Province) and other mountain states, defeated 300,000 defenders in Yehuling (now Wanquan Northwest, Hebei Province) and chased them to Huihe Fort. 12 13, the elite of 8 Jin Army was wiped out again in Huailai. Because Juyongguan was firmly defended, Genghis Khan took circuitous tactics and led the main force to enter the customs from Zijingkou and enter the surrounding capital (now Beijing). In the same year, we divided our troops and went south three ways, breaking dozens of counties north of the Yellow River and killing and plundering. 12 14, Jin Xuanzong offered a princess to make peace with Jin Bo, who retreated to Erlong (now Darino, Hexigten Banner, Inner Mongolia). Jin Xuanzong moved south to Bianjing (now Kaifeng, Henan), and the troops stationed in Zhongdu South rebelled against Jin, surrendered to Mongolia, and the Mongolian army re-entered the customs. 12 15, Zhongdu was captured and guarded by officials such as the great scholar Huachi, and Genghis Khan returned to Mobei. 12 17 years, Muqali was made King Taishi. Wang Gu, Hong Jila, Li Si, Wu, and the surrendered armies of Khitan, Nuzhen, Yi and Han were ordered to be in charge of the Central Plains and Han. Muqali gradually changed the previous practice of wanton killing and plundering, and failed to keep the land, focusing on seizing and using the armed forces of the Han landlords to attack the city. From 12 17 to 1229, except for the stone brothers and their sons, local armed leaders such as Yizhou (now Yixian County, Hebei Province), Dongping Yan 'an, Rong and Yidu Liquan successively descended to Mongolia, and most areas of Lianghe and Shandong were occupied by Mongolia. Mongolian bureaucrats and warlords who defected from all over the country often followed the official titles of the Jin Dynasty and were given the titles of Marshal and Provincial Officer, so as to continue to govern the army and the people in the sacrificial sites. This is the so-called Hou Shi.

1217 ~1218 years, Mongolia successively conquered the forest tribes in the northern territories such as Holly, Matu (in present-day Lake Baikal) and Jilikis, and conquered the Western Liao regime usurped by the Naiman aristocrat Qu Chulu. 12 19, on the grounds that hualamozi killed the Mongolian caravan and envoys, Genghis Khan made a personal expedition to the western regions, divided his troops and captured cities, and settled in his new capital Samarkand (now Samarkand, Uzbekistan). Maha, king of the thorn submodule, abandoned the city and fled. Genghis Khan sent Zhe Bie and Subutai to chase after him, and Maha fled to the island of Kigis Sea (now Caspian Sea) in Kuantian, where he died of illness. 122 1 year, Shu Chi, Chahetai and Wokuotai conquered the old capital Yulong Jiechi (now the Mongols in Kunya, Turkmenistan attacked Genqi and Tugur), Genghis Khan and his youngest son Tuo Lei divided their forces and captured the cities of Khorasan (now the area south of the Amu Darya River and north of the Hindu Kush Mountain), and then stationed on the Indian River, defeating the army of Zalandin, the new king of Aragis. 1223, Genghis Khan placed Lu Huachi and other officials to guard samar and led the army back to Mongolia. After plundering all regions of Persia, Zhe Bie and northern Jiangsu troops crossed Taihe Ridge (today's Caucasus Mountain) and invaded Qincha. 1223, in the battle of Alighi River (now north of zhdanov, Ukraine), defeated the combined forces of maharaja and Khin Chahan, swept the southern border of Volos, and turned to attack Lihe River (the Turkish name of Volga River).

1226, Genghis Khan once again sent troops to attack Xixia, took Jiangsu (now Jiuquan, Gansu), Gansu (now Zhangye, Gansu) and other States, wiped out the main force of Xixia near the Yellow River in Lingzhou (now southwest of Lingwu, Ningxia) and surrounded Zhongxing House (now Yinchuan, Ningxia). 1227, Li Bian, leader of Xixia Kingdom, surrendered.