In the past 100 years, the Central Plains region has divided the world into three.

In the vast region of the north, the Great Zhou Dynasty was strong and prosperous. At the same time, the two countries of Suxing and Nanfeng coexisted in the southern region. Among them, Nanfeng's national strength is the weakest, the border areas have been repeatedly attacked and plundered by Suxing, and gradually have the tendency to be embezzled, Nanfeng is a vassal to the Great Zhou for self-protection, and offers gold, silver and grain every year to seek the blessing of the Great Zhou. Since then, Da Zhou and Suxing have also become opposites.

Far north from the Central Plains, it is a treacherous place that cannot be reached by humans, and has not interacted with humans for thousands of years, and humans have described this place as the opposite of the heavenly realm--- the demon realm. Legend has it that the demon world is not under the control of the heavenly realm, and there are many demons and sinister.

In the southernmost part of the Central Plains, there is a brave and warlike tribe. According to legend, the men in the tribe have copper heads and iron foreheads, are invulnerable, brave and good at fighting, and never die. It is difficult for human armies to match it, and if the two sides resist, there will be rivers of blood. Some people also say that they are the descendants of Chiyou, after the defeat of Chiyou in the deer battle, the tribe was scattered, some of them belonged to the Yellow Emperor, and the people who did not want to belong to them were very numerous, in order to avoid the Yellow Emperor's pursuit and killing, they migrated all the way to the south, and finally the whole clan settled in the deep mountains and dense forests, and the Yellow Emperor did not dare to come out of the world. Since then, the Chiyou clan has been in the deep mountains for thousands of years to form their own system, and birds and beasts as a companion, with demons and monsters as neighbors, according to legend, its people are extremely vicious, annihilating human nature, the human world disdains to be with it, so it is called "demon clan", which means the same clan with demons.

Eighteen years ago, in the twenty-fifth year of Emperor Wen of the Great Zhou Dynasty, Suxing raised troops to invade Nanfeng, Nanfeng borrowed 100,000 troops from the Great Zhou to counterattack, the two sides fought on the border of Nanfeng for several months, the battle was fierce, tens of thousands of people were killed, and Suxing gradually became invincible.

The Great Zhou took the opportunity to send another army south to attack the weakly defended Suxing Capital, and the army was vigorous and resolute, breaking through the Suxing Capital City Jingcheng, killing the leader of the capital forbidden army who led the army to resist, and exterminating more than 100 people from his family and relatives, and no one dared to resist the people wherever they went.

That night, the army invaded the imperial city, killed the filial piety emperor Sikong Xianming and the crown prince Sikong Wenxuan, the queen in order to avoid humiliation with the princess Sikong Wenyu hanged herself in the dormitory, but the four-year-old second son of the Xiaoxian Emperor Sikong Wenlang and his biological mother Concubine Key, nowhere to be found, the Great Zhou army searched the palace inside and outside the palace, and in a fit of anger the palace slaves and royal relatives were all killed, and the blood inside and outside the palace flowed like a river, and the royal family was annihilated.

Since then, Suxing has broken the country.

After that, the balance of the three points in the Central Plains was broken. What followed was not a prosperous situation of tranquility and stability, but a long period of chaos and turmoil.

After the collapse of the Suxing Kingdom, it was controlled by the Great Zhou, but the armed forces that were originally hidden under the regime gradually emerged, and they all wanted to get rid of the control of the Great Zhou and establish a new regime, and there were often conflicts with the garrison of the Great Zhou army.

At the same time, the demon clan that had been dormant in the southern mountains and forests gradually prospered under the leadership of the new king Jiu Lieli, and was no longer satisfied with the status quo of survival in the hot and humid mountains and forests, and decided to go out of the mountains to replace Suxing with war and establish their own regime in the land of Suxing. As a result, a territorial scramble kicked off on this land originally called "Suxing".

On the eighth day of June in the twenty-eighth year of Emperor Wen of the Great Zhou Dynasty, the demon clan finally obtained the right to occupy this land, and a new country led by Jiu Lieli was established on the land of Suxing, with the name of "Youdu".

In the same year, Emperor Wen of the Great Zhou Dynasty collapsed, and Emperor Wu ascended the throne.

With the help of strong military force, Youdu pacified the domestic resistance forces, absorbed the original Suxing officials as officials again, and followed most of the original system of Suxing, and became stronger and stronger after several years of development.