The Khitan people, initially a different ethnic group from the Kumo Xi, yet sharing the same origins, were both defeated by the Murong clan and fled to the Songmo area. They gradually grew stronger and settled several hundred miles north of the Yellow Dragon. Their customs were quite similar to the Mohe people, and they had a penchant for raiding. When their parents died, they mourned loudly, yet regarded it as shameful. They would place the bodies in trees on the mountains, collected the bones three years later and cremated them, and while pouring wine as a sacrifice, prayed: "In the winter, there will be food in places where the sun shines. If I go hunting, I will catch many pigs and deer." They were rough and brutal, the fiercest among all the ethnic minorities.

During the Later Wei period, the Khitan faced attacks from Goguryeo, and over ten thousand households sought to submit to the Great Sui Dynasty and settled along the banks of the Baipi River. Later, they were harassed by the Turks, and another ten thousand households sought refuge in Goguryeo. In the fourth year of the Kaihuang era, the Khitan leader, Mo He Fu, paid a visit to Emperor Wen of Sui. In the fifth year of the Kaihuang era, all the Khitan people and their horses submitted to the Great Sui, and Emperor Wen of Sui welcomed them, allowing them to live in their original lands. In the sixth year of the Kaihuang era, the various Khitan tribes engaged in prolonged conflicts among themselves and also fought with the Turks. Emperor Wen of Sui dispatched envoys to reprimand them. The Khitan sent envoys to offer apologies and seek forgiveness. Later, several Khitan tribal leaders betrayed Goguryeo and led their people in submitting to the Great Sui. Emperor Wen of Sui welcomed them and resettled them north of Ke Xi Na Jie.

In the final years of the Kaihuang era, over four thousand households of Khitan people defected from the Turks and surrendered. At that time, the Sui Dynasty had good relations with the Turks, but ultimately lost the support of these distant refugees. Emperor Wen of Sui ordered that they be provided with food, arranged for the Turks to accept them, and sent them back to their old homes. Yet, they stubbornly refused to leave. The Khitan tribes increased in number, migrated northward in search of water and pasture, and finally settled two hundred miles directly north of western Liao, near the Hechen River. Their territory spanned five hundred miles from east to west and three hundred miles from north to south, divided into ten tribes. The larger tribes had up to three thousand warriors, while the smaller ones had only a few hundred. They grazed their livestock according to the seasons and availability of water and came together for warfare under the guidance of their tribal leaders. The Turkic Khan Shabolue sent Tudun Pandie to lead them.

The Shiwei were comparable to the Khitan. The Shiwei were situated north of the Khitan and were divided into five groups: Southern Shiwei, Northern Shiwei, Bo Shiwei, Shenmoda Shiwei, and Da Shiwei, lacking a unified leadership structure. The people were poor and weak, resulting in the Turks frequently sending three Tuduns to oversee them.

The Nan Shihui people live about 3,000 li north of the Khitan, where the land is low-lying and damp. In the summer, they move to the northwest to the Dabo and Qiandui Mountains, where the vegetation is lush and there are many birds and beasts, but also many mosquitoes. To avoid mosquitoes, the locals live in nests high up in the trees. Gradually, they divided into twenty-five tribes, each with a leader called "Yumo Fumanduo," similar to a chieftain. When the leader dies, his descendants inherit the position, and if there are no descendants, they select capable individuals. Their customs are that men wear their hair loose, women tie their hair up, and their clothes are similar to those of the Khitan. They ride ox carts, using bamboo mats as awnings, which somewhat resemble the felt carts used by the Turks. When crossing a river, they tie straw together to make rafts or use animal skins to make boats. Their horse saddles are made of woven grass, and the reins are made of knotted ropes. At night, they dig a hole in the ground and cover it with a bamboo mat, taking it with them when moving. They use pigskin for bedding and weave wood into mats. Women sit cross-legged. The climate there is very cold, the harvests are poor, there are no sheep and only a few horses, but they have plenty of pigs and cows. They brew alcohol, and their drinking customs resemble those of the Mohe. Their marriage customs involve the groom secretly abducting the bride after both families agree, then offering cattle and horses as a bride price, and finally returning the bride home. When the bride is pregnant, the groom takes her back to his family. Women do not remarry, as they believe a deceased man's wife would find it hard to get along with another husband. Each tribe builds a large shed together, where they place the deceased. They observe a three-year mourning period, during which they only cry four times a year. Their land lacks iron, and they have to import it from Goryeo. They have an abundance of sable skins.

Continue north for eleven days and you will reach North Shuwei, which is divided into nine tribes living around Tuheshan. Their tribal leader is named "Qiyinmohe Duo," and each tribe has three "Mohefu" to assist him in managing the tribe. The climate is colder there, with snow so thick it can bury horses. In winter, they move to the mountains and live in earthen caves, resulting in the freezing of many cattle. There are many roe deer there, and they mainly rely on hunting for a living, living on meat and wearing animal skins. They break open the ice, dive into the water to catch fish and turtles with nets. With thick snow covering the ground, they worry about falling into pits, so they travel on wooden planks. Their primary occupation is trapping sables, wearing hats made from fox or badger fur, and clothes made of fish skin.

Another thousand miles north, you will reach Boshuwei, where they live near Hubu Mountain, with a significantly larger population than North Shuwei, though the exact number of tribes remains unclear. They use birch bark to build houses, with other customs similar to those of North Shuwei.

I walked southwest from Boshuwei for four days and arrived at Shenmoda Shuwei. This place is named for its proximity to a water source. In winter, they all live in earthen caves to escape the biting cold.

Continuing northwest for several thousand miles, I eventually reached Dashuwei. The road conditions were particularly poor along the way, and the language was entirely foreign to me, making travel extremely challenging! However, this area is rich in sable fur and voles.

As for North Shuwei, they occasionally send envoys to offer tribute, but at other times, no one has visited there.

The historical records say: the troubles brought to the Central Plains by the Four Foreign Tribes have a long history, especially severe from the northern nomadic tribes. They have a large population, constantly rising, taking turns to dominate the borderlands. This is a long-standing issue that cannot be easily summarized. During the Five Emperors period, there were the Xunyu (a nomadic tribe); during the Xia, Shang, and Zhou periods, there were the Xianyun; during the Han dynasty, there were the Xiongnu; in the period of the Wei, Jin, and Northern and Southern Dynasties, the Wuhuan and Xianbei emerged; during the Northern Wei and Northern Zhou periods, there were the Rouran and the Turks. The leaders of these tribes, one after another, were all vying for power. They all lived by animal husbandry, relying on aggression and plunder to gain wealth, vanishing without a trace, drifting like clouds and scattering like birds. The wise ministers in the court debated strategies, while the brave generals on the borderlands discussed how to strike the enemy. However, circumstances are unpredictable, and power dynamics are ever-changing; whether to negotiate or go to war depends on the strength of the enemy, whether to submit or rebel depends on their rise and fall. When they are weak, they come to pay tribute, bowing and acknowledging their faults; when strong, they draw their bows and raid, alternating between submission and arrogance, their strength and weakness constantly shifting. They disregard the laws of the Central Plains dynasty, nor do they wear the hats of the Central Plains; they only care about interests, completely disregarding alliances. When they no longer reason with each other, becoming arrogant and oppressive towards the Central Plains, the strategies of negotiation, alliances, and military campaigns are well-documented in historical records. Thus, I will leave it at that.

After the decline of the Rouran, the Turks began to rise in power. During the period of the Ashina Khan, the Turks dominated the north. Their influence stretched from the old territory of the Donghu in the east to the borders of the Wusun in the west, boasting hundreds of thousands of archers stationed in the Yin Mountains region of Daizhou, threatening both the Northern Zhou and Northern Qi dynasties to the south. Both the Northern Zhou and Northern Qi struggled to resist them, both eager to negotiate peace and form alliances with the Turks. Ultimately, the Turks allied with the Northern Zhou, which ultimately led to the downfall of Northern Qi. After the founding of the Sui Dynasty by Emperor Yang Jian, the Turks' power grew even stronger. Armed with a formidable army, they readied themselves to march southward into the Central Plains. However, infighting among the Turks led to chaos, causing the Khan to flee, and the Qimin Khan requested to settle peacefully on the border. Taking advantage of the situation, the Sui Dynasty solidified its control, regained lost territories, aided in pacifying the remaining factions, and the Turkic forces grew stronger as a result. Until the Ren Shou period, the Turks refrained from invading the Central Plains or rebelling, maintaining their vassal relationship. It was not until the oppressive rule of Emperor Yang of Sui that the Battle of Yanmen Pass broke out. Subsequently, various bandits rose up, which only made the Turks stronger. While some heroes formed their own factions, they all sought to reconcile with the Sui Dynasty for stability. The Sui Dynasty set up administrative offices in Turkic territories to oversee local affairs, facilitating ongoing communication between the two, with the Turks offering tribute of gold, silver, treasures, and beautiful women. Throughout history, few ethnic minorities have ever been as powerful and ruthless as the Turks.

When the wise ruler of the Tang Dynasty ascended the throne and eradicated evil throughout the land, the Turks still did not grasp the changing situation. They continued to repeatedly invade the borders, leading their followers to breach the border fortresses, destroy the Yunzhou and the Daizhou, harass Taiyuan, plunder the Jingyang, and even let their horses drink by the Wei River. Emperor Taizong of Tang, with brilliant strategy and tactics, ultimately defeated this long-untamed enemy. He incorporated the vast lands they once occupied into Tang territory and counted the people who had previously lived in remote areas, an unprecedented achievement in history. This shows that although the rise and fall of empires follows certain rules, success ultimately depends on human ability and actions. To have without arrogance, to possess without dominating, to be as inclusive as heaven and earth, to nurture all things like yin and yang - this is the highest truth that is beyond words.