Whether in ancient times or now, rivers have played a very important role in the development and security of a country and region.
There were many wars in the Spring and Autumn Warring States periods, all of which took place near rivers. For example, the Mengjin alliance of King Wu of Zhou, such as the Battle of Hongshui of Song Xianggong and the Battle of Chengpu of Jin Wengong, all took place near the river and were named after the river. That is to say, war and rivers are inseparable.
The strength of a country is inseparable from the distribution of rivers. Most of the so-called prosperous times in ancient times occurred near rivers. For example, the Yellow Emperor, the Yan Emperor, and even the later Xia Shang Dynasty all originated from rivers. Yanhuang has Wei River, Xia Zhou has Luo Shui, and Yin Shang has Qi Shui.
Most of the places where the rivers are dense have fertile soil, and as the xia and Shang dynasties of the agricultural civilization, such places have a very favorable effect on agricultural development. Those so-called bitter cold places are often places where rivers are scarce, such as the Rongdi barbarians, why should they desperately attack the Central Plains? Because there are rivers in the Central Plains.
During the Spring and Autumn Period and the Warring States Period, all countries that lacked river resources were relatively weak. Countries with abundant river resources will be stronger. For example, the Yan, Wei, Korea, and Zhao states were relatively weak, and the Qin, Qi, and Chu states were relatively strong.
The State of Yan is located in the land of Youzhou, from the Bohai Sea in the east, to the Taihang in the west, to the grassland in the north, to the south near the State of Qi, the two major river basin systems of China, the Yangtze River and the Yellow River are not within the boundaries of the State of Yan, it can be said that its geographical location is very remote, for the "bitter cold land". For hundreds of years, it was difficult for the Yan state to dominate the Central Plains.
When the Jin Dynasty was strong, there were rivers such as Weishui, Fenhe, luohe and other rivers in the territory, during which the mountains and rivers intersected, the so-called Biaoli Mountain River, which dominated the princes for hundreds of years, can be divided into Han Zhao Wei and then, those rivers are fragmented, the three kingdoms each hold a piece, the defense system is more sparse, and finally broken by the Qin State.
It is only to say that the State of Wei of the Three Jin Dynasties occupied the north and south banks of the middle reaches of the Yellow River, and was at odds with Korea, but because it occupied part of the Kunhan homeland area, it could still be equal to the Western Qin State in a few years, and it could also be "Xuzhou Xiangwang" with the State of Qi. The State of Wei also attached great importance to the affairs of rivers, and also opened a chasm to divert water from the Yellow River to irrigate fertile land.
At that time, the nations often stationed heavy troops in the land of rivers, especially after Wu Yue became hegemonic, and the princes of the Central Plains recognized the importance of rivers, not only the State of Wei built a chasm, but also the State of Qi and other countries also built ditches. In agriculture, meandering rivers can promote the development of the agricultural economy; militarily, the wide distribution of rivers strengthens the country's military defense system. The State of Qi once built the starting point of the Great Wall on the banks of Jishui, which can be defended and Jishui can also be defended.
The State of Qi is the so-called "Taishan Mountain in the south, Langya in the east, Qinghe River in the west, and Bohai Sea in the north", although there are only two major river systems in the territory, the Yellow River and Jishui. However, the western Jishui is connected to the Great Wall, the Yellow River and the Bohai Sea in the north, the Taishan and Yishui in the south, and the Yan and Lu states in the north and south of the Qi state, all of which cannot oppose the Qi state. In the West, there are rivers and the Great Wall, and if the Qi state is not strong enough to meet the strength of Yanlu, it can be strong alone and not be invaded by the Western powers.
The southern Chu state is completely in the Yangtze River basin, the Yangtze River is the largest river in China, there are many diversions in the land of the Chu state, irrigation washes away the land of the Chu state for thousands of years, here there are not only many rivers, but also many lakes. In the later period, when the Chu state moved north, there were Huai, river, and Ji water running through it, and most of the Chu state controlled these rivers, that is, it mastered the important lifeline, and it was not easy to be completely annihilated. Even after Qin attacked the capital of the Chu State, the Chu State could still migrate several times, and finally even destroyed the Army of the Qin Dynasty, and many of the core forces came from Chu Land.
Finally, the State of Qin, the State of Qin not only has the KunShan Mountains, but also the Natural Danger of the Yellow River, and the rivers such as Weishui in the later period are controlled by the State of Qin, and the State of Qin sets up military fortresses on the borders of these rivers and sets up a mobile and flexible military defense system, thus becoming its great power. The Qin state also attaches great importance to rivers, and the reason why the Qin state first destroyed Korea is actually precisely because Korea and the Qin state are connected by Weishui, and the attack and destruction of Korea runs through both sides of the Weishui River, which is more conducive to the external development of the Qin state.
Later, the State of Qin attacked the State of Chu and the State of Wei, and often dug ditches to break through the city, such as flooding the girder and flooding the city, and hundreds of thousands of troops were killed in it. It can be seen that the role of the Qin state on the river is quite thoroughly studied. Rivers are vital to the development of a country, so it can be said that whoever gets the river wins the world!