In the autumn of 1009 A.D., Li Gongyun, the former commander of the former Lê Dynasty and the former commander of the Zuo Qinwei Palace, usurped the throne and established the Li Dynasty by taking advantage of the former Lê Dynasty's heir Youchong, and the country name was "Da Qu Yue" (??). iC?Vi?t）。 In the sixth year of Chongxing Dabao (1054), Li Dynasty Taizong Li Foma collapsed, and the Holy Emperor Li Rizun ascended the throne and changed the country name to Dayue (???). iVi?t）。 In 1225, Chen Cheng, the assistant imperial lieutenant who held the power of the Li Dynasty, and Chen Shoudu, the commander of the palace, forced the young empress Li Zhaosheng to give way to Chen Cheng's son Chen Ju and established the Chen Dynasty, with the state name still Dayue.

The territory of the early kingdom of Da Viet was "bordered by China to the north, roughly the same as the border between Vietnam and China today, and bordered Cham on the south by Hengshan (in present-day Yijing Province)." The western and northwestern regions are the homeland of various tribes such as Tu, Dai, and Miao. They still maintained their independence, and only occasionally paid tribute to the Ly Dynasty" (Vietnam Tao Wei Anh, History of Vietnam). Its territory is roughly the Red River Delta, the birthplace of "Cochin" under the rule of Chinese dynasties, and is only 1/4 of the territory of modern Vietnam.

Representing the interests of feudal aristocrats, bureaucrats, and large landowners, the Great Yue State had a period of 1,000 years of northern China, with developed politics, economy, and culture, and a relative advantage in national strength. At the same time, the ruler used the words similar to that of the Chinese monarch, such as "being ordered by heaven to be in the middle of Xia, at home and abroad, and not surrendering", and actively used troops to use troops abroad, "using Xia to change Yi", and successively launched wars of aggression against neighboring countries in the west, northwest, and south directions, and expanded their territory.

The striking feature of the expansion of the Great Viet Kingdom is that it was the result of a mixture of official planning and spontaneous consciousness of the people. In order to maintain the long border line that they were constantly advancing, the Vietnamese adopted the method of military cantonment, recruited landless displaced people to reclaim the famine, and gave the poor people at the bottom who had no place to stand in the past a way out.

The Ly Dynasty was a feudal state in the history of Vietnam that enriched the country and strengthened the army, attaching importance to agriculture, reorganizing armaments, implementing conscription, compiling laws, and establishing a solid foundation for independence. The emperors of the Li Dynasty did not forget to "conquer and occupy", or sent troops to "conquer", or "drove the imperial expedition". In the winter and December of 1020, Li Gongyun "ordered the Heavenly King Foma to attack and occupy the city", and fought from Buzheng Village (now Guangzhi) to Longbi Mountain (now Pingzheng County, Guangping). In 1044, Li Taizong drove his own expedition, invaded the city in the south, "beheaded 30,000 ranks", "beheaded the lord in battle", "captured 5,000 people alive, and obtained more than 30 elephants. The corpses of the Zhan people were killed by the officials and soldiers, and the corpses piled up in the wilderness", "then entered the city of Buddha Oath (the capital of the city, near present-day Hue) and captured the lord's wife and concubines and palace maids" ("Compendium of Yue Shi Tongjian") and escorted Huilong. In 1069, Li Shengzong personally conquered the city, with Li Changjie as the vanguard, captured the royal capital of Zhancheng, forced Zhancheng to cede the northern territories of Li, Buzheng and Maling, and expanded the territory of Vietnam southward to the northern areas of present-day Quang Binh and Quang Tri. In the northwest, the Tuojiang River basin is inhabited by an independent tribe. Vietnam calls it a bull roar. "Xinghua Fengtu Ji" records: Niu Roar speech, writing and mourning with "Niu Roar area people are unwilling to accept the rule of Vietnam, Li Taizong Li Foma began to "crusade" Niu Roar country, and constantly plundered people, cattle, horses, elephants to bring up the dragon, in 1119 AD, Li Renzong "captured his cave chief Wei Peng and other hundreds of people...... And also.

The rulers of the Li Dynasty took advantage of the war between the Song Dynasty and the Liao and Western Xia Dynasty and their inability to look south, and constantly invaded the Song Dynasty's frontiers and encroached on the Song Dynasty's territory. After Li Gongyun defeated the Dali army in 1014 in Phuong Lim Prefecture (Viet Chi, Vinh Phu Province, Vietnam), he expanded to the north and northwest, and finally occupied the bureaucratic areas of present-day Vinh Phu Province, Ha Xuan Province and North Tai Province. The Song Dynasty has always tolerated, believing that "Jiaozhou is miasma, Yizhou is dangerous, if the army is raised, there will be many casualties." And the ancestors opened up a vast territory, if this should be guarded, why bother to mobilize the people and covet useless places!". At the end of 1075, Li Renzong and Li Qiande sent Li Changjie, Zong Kang and others to lead 100,000 troops to invade China on a large scale, capturing Qinzhou (now Ningshan), Lianzhou (now Hepu) and Yongzhou (now Nanning) and other places. Because the Yongzhou magistrate Su Mian led the people to resist stubbornly, Li Changjie led the army to brutally slaughter the city, and the residents were killed "more than 58,000 people" and "more than 100,000 dead" in the two prefectures of Qinlian, and "captured the people of the three states and returned". The Song Dynasty army repeatedly counterattacked southward, but was finally defeated by Vietnam in a protracted war (Vietnam was at a disadvantage in national strength compared to the Song Dynasty, and did not occupy the time of heaven, but had the power and people of the land. Militarily engaged in a protracted war, taking advantage of the complex terrain and hot climate to wear down the opponent, and generally retreating to the Red River line before turning to a counterattack), the incompetent Song Dynasty was forced to give Guangyuan Prefecture, Menzhou, Sumao Prefecture, Hulang County and other places to the Dayue Kingdom in order to seek peace.

Judging from these histories, Vietnam's aggressiveness has existed since ancient times, and it has been in the same vein. As a small country living around a behemoth like China, it has not been cut off from civilization like those same small countries and ancient countries in the long river of history, because of this national habit. The regimes and civilizations of the Western Xia, Nanzhao and other ethnic minorities have all been lost to the long river of history, and the surviving civilizations have basically been wiped out, expelled and assimilated by China, except for the two major masters of Sanhan and Japan.

The main axis of China's history is still the history of the resource competition between the Han nationality and a small number of nomadic peoples in the north, and the struggle with the nomadic powers, which have a vast territory in the north and strong military mobilization capabilities, runs through the Han regimes of all dynasties after the Qin Dynasty.

Those small countries and southwestern peoples who basically have little combat power and can threaten the core area of domination cannot enter the emperor's eyelids at all. Like a mosquito, it makes a little buzzing sound at most, which makes China's rulers feel bored and agitated, but it is absolutely impossible to produce restlessness or even fear.

In order to completely kill these mosquitoes, the crossing people decided to kill the killers, and when they were fully prepared, they advanced by sea and land, and wiped out all the mosquitoes in the small Southeast Asian countries and around China in one fell swoop. Free up your hands and feet to fight a thorough decisive battle with the old enemy in the north, permanently solve the coveting of China by the horseback people, and completely rule the whole of Asia.

Bringing your own dry food is not the style of crossing the crowd, and eating the enemy is an advanced strategy to feed the war, as long as you prepare enough manpower and material resources, you can completely eliminate all mosquitoes.

When discussing how to formulate the overall business strategy of Southeast Asia, the opinions of the people were divided into two factions, one was the quick victory faction based on Wang Xinyu's opinion, as long as a few thousand elite soldiers were eliminated, all the high-ranking nobles in the capitals of several large countries could break all resistance and completely occupy this fertile land. One faction is the gradualist faction based on Bai Jia's opinions, which needs to continue to operate for many years, dilute the indigenous population through immigration, assimilate the indigenous people through education, and integrate all local families into the colonial economic system through trade and promoting the development of local industry and agriculture, so as to solve the problems and unstable factors.

In the end, Li Ji unexpectedly chose the gradual opinion, but changed the period from fifteen years to five years. Unlike the policy towards Japan, the policy towards Southeast Asia was more radical and brutal, and instead of choosing to support agents like the Taira clan and infiltrate through Buddhist temple organizations, it completely relied on economic hegemony and military hegemony to subdue the local upper class.