The Qin Dynasty (221 BC) was the first multi-ethnic absolutist centralized dynasty in Chinese history. A series of measures taken by Qin Shi Huang to consolidate the centralization of absolutist power had a significant impact on later generations. After the unification of Qin, in order to defend against the southern invasion of the Xiongnu, on the basis of connecting the original Great Wall in the north of the three kingdoms of Qin, Zhao and Yan, it extended to the east and west to build a city defense from Lintao in the west to Liaodong in the east. This is the famous Great Wall. The tyranny of the Qin rulers led to the outbreak of the Peasant War and the demise of the Qin dynasty.

The Han Dynasty was a dynasty in Chinese history that emerged after the short-lived Qin Dynasty, which was divided into two historical periods: the "Western Han Dynasty" (202 BC - 8 BC) and the "Eastern Han Dynasty" (25 AD - 220 AD).

The Western Han Dynasty was founded by Liu Bang, the ancestor of the Han Dynasty, and the capital was Chang'an, and the Eastern Han Dynasty was founded by Liu Xiu, the Emperor Guangwu of the Han Dynasty, and the capital was Luoyang. During this period, there was a brief new dynasty (8 AD-23 AD) in which Wang Mang usurped the Han Dynasty and established itself. In addition, some scholars also include Shu Han as part of the continuation of the Han Dynasty, so that the Han Dynasty fell in 263, but most accounts attribute the Shu Han regime established by Liu Bei to the History of the Three Kingdoms.

During the Han Dynasty from Gaozu of the Han Dynasty to the Wenjing period of the Han Dynasty, its economic strength rose sharply and became the first empire in the East, and it was called the two major empires along with the Western Romans. The major powers of Central Asia and the Western Regions were also afraid of it. By the time of Emperor Wu of the Han Dynasty, the Han Empire had become the most powerful empire in the world, and the Xiongnu Empire was defeated and fled northward.

Zhang Qian's mission to the Western Regions opened the famous "Silk Road" for the first time, opening the passage of trade between the East and the West, and China became the center of the world trade system until the Mongol rebellion more than a thousand years later. It is precisely because of the prestige of the Han Dynasty that foreigners began to call the Chinese "Han people", and the Han Dynasty people were happy to call themselves so, and "Han" has since become the eternal name of the Chinese nation.

At the beginning of the Han Dynasty, Liu Bang, the ancestor of the Han Dynasty, always said that Zhengshuo was the water virtue, and when Emperor Wu of the Han Dynasty, he corrected Shuo to the earth virtue, until Wang Mang established a new dynasty, and then adopted the statement of Liu Xiang Liu Xin and his son, thinking that the Han Dynasty belonged to the fire virtue. After Emperor Guangwu of the Han Dynasty recovered the Han Dynasty, he officially recognized this statement, and since then established the Han Dynasty Zhengshuo as Huode, and the Eastern Han Dynasty and later historical books such as the Han Book and the Three Kingdoms have adopted this statement. Therefore, the Han Dynasty is sometimes called "Yan Han", and it is also called "Yan Liu" because the surname of the emperor of the Han Dynasty is Liu.

The establishment of the second great unified dynasty of China. In the early period, the capital was Chang'an, also known as the Western Han Dynasty and the former Han Dynasty, and in the later period, the capital was Luoyang, also known as the Eastern Han Dynasty and the Later Han Dynasty. The Han Dynasty was a strong and prosperous dynasty in the early days of China's feudal society, which inherited and consolidated the unified country that began with the Qin Dynasty, with a prosperous economy, strong national strength, and a happy people, presenting a scene of peace and prosperity. During this period, China has always stood tall in the world as a world power. As a result, the Han Dynasty is regarded as the first golden period in Chinese history. The Western Han Dynasty passed on a total of 14 emperors, and it took 210 years before and after.

The Han Dynasty was an important period in the history of the development of the Chinese nation, and it was during this period that the Han nationality, the core of all ethnic groups in China, emerged. Since Qin Shi Huang unified China, the cultures of various countries in the former Warring States period have penetrated and integrated with each other, and by the time of the Western Han Dynasty, China gradually tended to unify in many aspects such as the code system, language and writing, culture and education, and customs and habits, constituting a common Han culture.

Since then, the various ethnic groups in China have emerged as a unified Han nationality. The Han Chinese and the surrounding minorities were members of the multi-ethnic state of China during the Han Dynasty. Due to its high degree of civilization, the Han nationality has always been in a dominant position among the fraternal ethnic groups in China, which is the result of historical development and natural formation. Although the names of dynasties after the Han Dynasty have changed, the status of the Han nationality as the main ethnic group in China has never changed.

From the establishment of Wei by Cao Pi in 220 A.D. to the unification of Sui in 589 A.D., it was a period of division and great ethnic integration of feudal countries in Chinese history.

After the heavy blow of the Yellow Turban Uprising, the Eastern Han regime has existed in name only. In the course of suppressing the uprising, a number of military groups emerged that divided one side. Cao Cao defeated Yuan Shao at Guandu and basically unified the north. In the Battle of Chibi, Cao Cao was defeated by Liu Bei and Sun Quan and retreated to the north. The positions of Sun Quan and Liu Bei were consolidated.

In 213, Cao Cao proclaimed himself Duke of Wei and established the state of Wei. In 220, his son Cao Pi was proclaimed emperor; in 221, Liu Bei was proclaimed emperor Jianhan, known as Shu Han in history; in 222, Sun Quan was canonized as the king of Wu by Cao Pi and established the state of Wu, and in 229 he was proclaimed emperor, and the situation of the Three Kingdoms was formed. During the Three Kingdoms period, the economies of all countries developed.

In the later period of the Three Kingdoms, the power of Wei became increasingly powerful. In 263, Wei destroyed Shu Han. In 265, Sima Yan seized the Wei regime and established the Jin Dynasty, known as the Western Jin Dynasty.

In 280, the Western Jin Dynasty destroyed Wu, ending the situation of the Three Kingdoms. The unification of the Western Jin Dynasty was short-term, due to the increasingly acute class contradictions and ethnic contradictions, the internal migration of ethnic minorities and displaced people in various places continued to revolt and resist, which finally led to the demise of the Western Jin Dynasty.

After the fall of the Western Jin Dynasty, the imperial family Sima Rui established power in the south of the Yangtze River, known as the Eastern Jin Dynasty in history. The rulers of the various ethnic groups in the north successively established many countries, known as the Sixteen Kingdoms in history.

In 383, the Eastern Jin Dynasty won the battle of Huangshui between the former Qin and the Eastern Jin Dynasty, which unified the Yellow River Valley, and soon after, the former Qin collapsed, forming a situation of confrontation between the north and the south. In the south, after the Eastern Jin Dynasty, there were four dynasties of Song, Qi, Liang and Chen, known as the Southern Dynasties, and in the north, there were five dynasties of the Northern Wei, Eastern Wei and Western Wei, Northern Qi and Northern Qi, known as the Northern Dynasties.

During the period of the Northern and Southern Dynasties, Jiangnan was developed, and there was a great integration of various ethnic groups in the north. The reforms of Emperor Xiaowen of the Northern Wei Dynasty further promoted the integration of ethnic groups.

During the period of the Three Kingdoms and the Jin Dynasty and the Northern and Southern Dynasties, due to the great integration of various ethnic groups and the economic development of the North and the South, science and culture were further developed, and world-leading achievements were made in many fields.

The Northern Zhou unified most of the region, and the remaining Chen army was weak. In 581 AD, Yang Jian usurped the throne of the Northern Zhou Dynasty. Yang Jian's usurpation of the throne not only benefited from the accident of the collapse of Emperor Xuan of the Northern Zhou Dynasty, but also luckily because of the close ministers and ministers, so as to control the center. Yang Jian relied on the powerful imperial power accumulated by Emperor Wu and Emperor Xuan of the Northern Zhou Dynasty to consolidate the foundation of his rule and finally usurp the national throne of the Northern Zhou Dynasty. In the ninth year of the emperor's reign (589 AD), Emperor Wen of Sui went south to destroy Chen.

Emperor Wen of Sui and Yang Jian carried out a lot of reforms. Politically, he strengthened the feudal centralized power system by establishing the political system of "three provinces and six ministries"; economically, he adopted the system of acres and acres since the Northern Dynasties, which promoted the development of agriculture. Culturally, Emperor Wen of Sui admired Buddhism.

Soon after Yang Guang, Emperor Yang of the Sui Dynasty, ascended the throne, he carried out excessive and brutal expropriation and rule, which led to a large-scale peasant uprising and the collapse of the Sui Dynasty's rule.

Li Yuan Li Shimin raised troops only in Taiyuan, after entering Guanzhong, in 618 AD, Li Yuan established the Tang Dynasty. After that, Li Yuan and Li Shimin, the Tang Dynasty gradually defeated many separatist forces at the end of the Sui Dynasty, unified them, and ended the chaos at the end of the Sui Dynasty. After Li Shimin ascended the throne, he conquered and destroyed many foreign enemies such as the Turkic State, the Tuyuhun State, the Western Regions States, and the Xue Yantuo State, and expanded to occupy Hetao, Monan, Mobei, Western Regions, Annan and other places, and established rule in these regions, so that the Tang Dynasty began to rule these regions for a long time.

Politically, the Tang Dynasty perfected the political system of "three provinces and six ministries", improved the education system, and formulated more complete laws. Economically, the implementation of the system of land equalization, the reward for land reclamation, and the stability of the peasants' livelihood enabled the peasants to further get rid of the semi-serf-like state of personal dependence in the Wei, Jin, and Sui dynasties, and achieved a relatively independent status.

The Tang adopted a liberal policy towards commerce, convenient transportation, the unification of currency and weights and measures, and the unprecedented activity of commodity trade and cultural exchanges. Chang'an, the capital city, has as many as 220 Chinese and foreign businessmen, and is a place where envoys and business travelers gather, and it is also an open international metropolis.

The handicraft industry of the Tang Dynasty is also very developed, there are both government-run workshops and private workshops, and silk, gold and silverware, and "Tang Sancai" have reached the point of perfection. The Tang Dynasty no longer "respected Confucianism alone", but allowed Confucianism, Buddhism, and Taoism to be promoted simultaneously, which also objectively enhanced political openness and ethnic integration, and promoted the prosperity of economy, culture and art.

The Tang Dynasty was a powerful country, its prestige spread far and wide in East Asia, and there were few foreign troubles, and most of the peasants were exempted from military service. In such a relatively fresh and free air, the people of the Tang Dynasty were full of self-confidence and formed a high-spirited, bold and cheerful, healthy and progressive style in culture.

Before and after the Tang Dynasty, whether it was prose, poetry, legends, architecture, music, painting, sculpture, acrobatics, dance, calligraphy and arts and crafts, all made rapid achievements and achieved prosperity far beyond that of the Qin and Han dynasties. The Tang Dynasty dared to absorb foreign cultures and integrate the cultures of various ethnic groups in China, and its literature and art had distinctive characteristics of the times in both content and form. The culture of the Tang Dynasty spread far and wide, and had a profound influence on Iran, Japan, Goryeo, the South Asian subcontinent, Arabia, the Eastern Roman Empire, and even Africa.

The Tang Dynasty was severely weakened by the internal strife and the Anshi Rebellion. After quelling the rebellion, the three towns of Hebei were annexed to the Tang Dynasty. According to historian Zhang Guogang's monograph "A Study of Tang Dynasty Domain Towns", in most of the second half of the Tang Dynasty, most of the feudal towns were not divided, only a few feudal towns such as Heshuo were divided, but the policies and decrees of the Tang Dynasty were also implemented to a certain extent, "it is necessary to use the authority of the imperial court officials to secure the military situation", and the secession of feudal towns has also been lifted. At the end of the Tang Dynasty, during the Huangchao Rebellion, there was a general division of feudal towns.

In the late Tang Dynasty, industry and commerce made great progress. "Silk cloth for clothing, linen cloth for sacs, felt hats for covers, leather for belts, inner Qiu white urns, Duanxi purple stone inkstone, no noble and lowly universal in the world."

The official order of the Tang Dynasty prohibiting officials from doing business was conducive to the development and growth of ordinary industrialists and merchants. The official of the Tang Dynasty also ordered that "it is advisable to order all merchants to prosper and peddle, and no exchanges shall be prohibited", which is conducive to the development of commerce.

Compared with the Warring States period, Hua Feng felt that the prosperity and development of the Tang Dynasty was more unique.