The state of Chu has a history of eight hundred years, except for the nearly three hundred years before the Spring and Autumn Period, the next five hundred years can be described as magnificent. The State of Chu was never a weak country, and even in the Western Zhou Dynasty, Zhou Tianzi led wang shi on an expedition, but could not completely conquer the State of Chu, but died unexpectedly on the way home. Although the State of Chu was in a barbaric land, its national strength had never been inferior to that of the princes of the Central Plains. More importantly, the State of Chu was in the south, and was rarely affected by the disputes of the Central Plains princely states, so it could quietly cultivate and develop in the south until the spring and autumn Warring States era.
During the time of King Wu of Chu of the Chu people, an iron-fisted policy was pursued. The State of Chu no longer shrank to the barbaric land in the south, and the "Blue Wisps of the Road to Enlighten the Mountains and Forests" taught by the ancestors of the State of Chu in those years made the kings of the State of Chu suffer a lot. The people of the Central Plains have fertile land and advanced civilization, and the Chu people can naturally have it. King Wu of Chu established himself as king, no longer afraid of the princes stationed on the Jianghan Plain of Zhou Tianzi, and the Zuo Biography says: "The king of Chu Wu overcame power and made Dou Yinzhi." Kill them by rebellion. Shifting power to that place, making Yan Ao Yinzhi", this war of annihilation against the power of the country, the battle of the Chu people against the Hanyang Zhuji.
With the efforts of the Chu people from generation to generation, the Chu people gradually fought from the south to the north, and even won the victory on the edge of the Tianzi King's city of Luoshui to show the domineering spirit of the Chu state. The Hundred Years' War of Jin and Chu made the princes of the Central Plains realize the strength of the south, and the states of Zheng, Song, and Chen turned against each other and became allies of the State of Chu. From this period onwards, the Chu people also began the curtain of alliances and attacks on the Central Plains. It can be said that during the reign of Jin and Chu, for a long time, the people of the State of Chu did not encounter enemies, and countless small princely states in the Central Plains were besieged, and the Chu State was only attacked by the State of Wu, which belonged to the south, only by the state of Wu, which belonged to the south. Both the State of Wu and the State of Yue could not pose a really fatal threat to the State of Chu, and even in the last days of the Warring States, the land of Wu Yue was owned by the Chu people.
The Chu people may have thought that it was to ally with the Qin state in the west of the Jin state to weaken the power of the Jin state. However, the people of the State of Chu may not have thought that this low-key Qin State before the Spring and Autumn Period will eventually become a major problem for the State of Chu. However, the threat of the State of Qin to the State of Chu did not come from the State of Qin, but still came from the land of the Three Jins, the weakest vassal state of Korea. It took at least a hundred years for the State of Qin to open up the road to the east, and formed an oppressive trend with the State of Chu in the south against the Three Jins region. But the problem also arose, the territory of Korea in the Three Jins, including the famous land of Kunhan, was the best way to break through the Central Plains, and its strategic position was quite important.
Fan Sui once said: "Qin and Han only have terrain, and they are as wrong as embroidery." Qin has Han, Ruomu has beetles, and people are sick confidants. The world has changed, and the qin victims are greater than Han. The king might as well take han. Later, the State of Qin launched a large-scale war against Korea and the Battle of Tianzi Wangcheng, and it was this strategy that laid the foundation for the later Qin State. Zhang Yi also said: "What Qin wants is as weak as Chu, and those who can be weak are like Han." If it is not that Han can be stronger than Chu Ye, its terrain is also", which means that the important hinterland between Qin and Chu, and even the land of Korea can contain the way of the Chu state to the north, and later the battle of Lantian and the battle of The Cliffs between the Chu people and the northern princes, the participation of Korea has played a very crucial role.
The understanding of the land of Korea by the Qin people is obviously clearer than that of the Chu people. When the Qin people attacked Yiyang that year, due to heavy casualties, although they successfully captured Yiyang, they were still worried about the Chu state in the south, and they also specially sent people to the Chu state to deceive the Chu state to give the chu state the land of Hanzhong. If you don't rescue South Korea, it is enough, the Chu people actually want to have two sides and three knives, pretending to promise South Korea: "May the great powers wantonly go to Qin, and the evil Yi will martyr Han with Chu", the result is that the Koreans are bitterly waiting for the Chu army, fighting alone for many days, and finally failing miserably. After the Qin state occupied Yiyang, it led a large army to continue south and attacked the new city of the Chu state. The land of Korea, for Chu, can be described as the key.