The Battle of Baiju was a far-reaching war between Wu and Chu during the Spring and Autumn Period, in which 30,000 Wu troops defeated 200,000 Chu troops. The emerging power of wu in the south captured the capital of the old power of Chu and nearly destroyed the state of Chu. After this battle, the State of Wu became the hegemon of the south, while the State of Chu was devastated and fell into a period of dormancy for a long time. However, to analyze the reasons for the victory or defeat of the Battle of Baiju, it is important to consider the strategy and tactics of the two sides on the battlefield, but this war is far from being as simple as a simple confrontation between the two armies.

The "International Background" of the Wu-Chu War
The war between Wu and Chu was actually a continuation of the Jin-Chu struggle for hegemony. The Jin and Chu states had been competing with each other since the rise of The Duke of Jin, and by the late Spring and Autumn Period, the State of Chu had begun to be on the defensive in an all-round way, but the State of Jin had also been exhausted by years of wars for hegemony. Therefore, the Jin state began to support and co-opt the emerging power of Wu in the south to achieve the purpose of containing and dragging down the Chu state. Therefore, the Wu-Chu struggle for hegemony was essentially a hegemonic war between the Chu state and the agents supported by the Jin state in the south.
A key figure in the rise of the State of Wu and the Wu-Chu War was King Shoumeng of Wu. After succeeding to the throne, he aspired to enrich the country and strengthen the army, and to get rid of his status as a vassal of the Chu state. Therefore, in the first year after he succeeded to the throne, he personally went to see Zhou Tianzi and confessed his ancestors to the sect, although Zhou Tianzi in the late Spring and Autumn Period actually had no strength at all. However, through this action, Shou Meng sent a political signal to the princes of the Central Plains, especially the princes with the surname Ji led by the Jin State, creating conditions for the later Jin-Wu alliance.
After that, the State of Jin sent the father and son of Wu Chen, who had defected from the State of Chu, to the State of Wu, bringing chariots and imperial hands, and teaching the Wu people who were not good at land and vehicle warfare in the south how to use chariots. The State of Wu also learned the method of battle, and its military strength began to grow stronger, and it also had the confidence to compete with the State of Chu for hegemony.
From the second year of Shou Meng's succession, the State of Wu launched a challenge to the State of Chu, first attacking allies or vassals of the State of Chu to test the response of the State of Chu. At the same time, the great powers of the Central Plains, led by the State of Jin, also actively cooperated with the military operations of the State of Wu, and even did not hesitate to send troops to help.
In 576 BC, the State of Wu began to participate in the alliance of the princes of the Central Plains and continued to actively integrate into the anti-Chu alliance. Later, the State of Wu participated in the Alliance many times, and in 563 BC, King Shoumeng of Wu even personally met with the monarchs of the Central Plains princes such as the State of Jin. A good "international environment" was established for the war for hegemony between the State of Wu and the State of Chu.
It can be seen from this that the Battle of Baiju between Wu and Chu cannot simply be viewed as a scuffle between princely states, this is a war of hegemony between the anti-Chu alliance and the Chu State and its vassal states, and the international diplomatic situation of the Chu State at that time was very bad, and the overall strength was weaker than that of the Jin State, and the increasing rise and provocation of the State of Wu made the Chu State suffer from the enemy, so the international situation before the Battle of Baiju determined that the comparison of forces between Wu and Chu was not so large.
The "Battle of the Father of Chickens" and the "Six Years of Fatigue" reversed the strategic situation between the Chu and Wu states
If it is said that during the reign of King Shoumeng of Wu, he won a good international situation for the State of Wu and formulated the correct line of competing with the State of Chu for hegemony. After the death of King Shoumeng of Wu, his successors began a war of hegemony with the Chu state along this path. The focus of the two sides was the competition in the Jianghuai region, and the Chu state occupied the Jianghuai region and could always suppress the Wu state, so the Wu state had always been eyeing the Jianghuai region.
In 519 BC, wu and Chu once again fought for control of the Jianghuai region, this time the state of Wu defeated the state of Chu in the Battle of Jifu. After this battle, the strategic situation of Wu and Chu began to reverse, and the Chu state lost its strategic initiative and began to gradually withdraw from the Jianghuai region. The State of Wu, on the other hand, could attack and retreat, and gradually controlled and eliminated the vassal states of the State of Chu in the Jianghuai region, further expanding its strength.
In 512 BC, King Lu of Wu followed the advice of Wu Zixu, who had fled from the State of Chu to the State of Wu, and adopted the strategy of dividing the troops into three routes and attacking the State of Chu in turn, for a time the State of Chu had no Wu divisions, and the Chu army was exhausted by the harassment of Wu soldiers. This strategy was implemented for six years until the outbreak of the Battle of Baiju.
After repeated tug-of-war, in 519 BC, thirteen years before the Battle of Baiju, the State of Wu controlled the land of Jianghuai through the Battle of Jifu and began to occupy the strategic initiative, and the strategy of dividing its divisions and taking turns to attack Chu from 512 BC effectively exhausted the chu army and people, and at the same time plunged the Chu state into a more passive position. At this stage, although the State of Chu still had some advantages by virtue of the large number of people in the land, the real strategic initiative had been surrendered, and the State of Wu began to plan the final war against Chu, which was later the Battle of Baiju.
The comparison of the real strengths of the two sides in the Battle of Baiju is actually not as big as imagined
In 506 BC, the final decisive battle between Wu and Chu was finally staged, and the Wu king Yan Lu led 30,000 elite Wu troops to attack the Chu state together with the combined forces of Cai and Tang (in fact, it was of a surprise attack). The State of Chu was led by the ruling Ling Yin Zichang (Nangwa) with 200,000 troops to resist (return reinforcements). It seems that the strength of the two sides is still very different, and the ratio of troops has reached 1:6, but in fact, the gap between the two sides is not as large as imagined.
The capacities of the ruling classes on both sides vary greatly. At this time, the monarch of the State of Wu was The King of Wu, who was young and powerful, and he had made great contributions to the Battle of The Father of chickens and had rich military experience. The Chu state reigned by the young King Of Chu Zhao (about 14 years old), who had no experience in governing, and the state administration was basically controlled by Ling Yinzi. Among the important courtiers on both sides, Wu Guo had Sun Wu's leading soldiers who wrote sun tzu's art of war, supplemented by Wu Zixu, who was extremely capable. On the other hand, the State of Chu, from the beginning of king Chu Zhao's father, King Chu Ping, was chaotic in state affairs and mutilated Zhongliang, and Wu Zixu was forced to join the camp of the State of Wu, and the greed and cruelty of the ruling son at that time, who was often known for his greed and cruelty, not only forced the people to revolt and rebel at home, but also because of the extortion of the monarchs of the vassal states and the unjustified detention of the kings of the States of Cai and the State of Tang, causing the allies of the two Chu states to turn to spontaneous support for the State of Wu and the State of Chu.
Wu Guo took the absolute initiative in the strategic situation. Because of the loss of the strategic area of Jianghuai, the State of Chu was actually unable to launch a large-scale active attack on the State of Wu for more than ten years, but instead adopted a passive defensive strategy of building a city on the border. The State of Wu not only marched westward vigorously, controlling and annexing many vassal states of the State of Chu, but also had certain influences such as Cai and Tang who also supported the State of Wu. The "six years of fatigue" strategy also made the Chu army exhausted and demoralized. Therefore, the State of Wu, which occupies the strategic initiative, is far from being as large as the simple disparity in the comparison of troop numbers in terms of real strength.
The strategy and tactics of the Chu army were defeated. At the beginning of the war, Ling Yinzi, the ruler of the Chu state, misestimated the international situation (in 506 BC, the 18th Route Princes would conspire to cut down Chu) and sent troops to attack the State of Cai, and the State of Wu took the opportunity to attack the State of Chu in the name of rescuing the State of Cai, and entered the State of Chu from the northeast of the weak defense of the State of Chu. After learning of the entry of the Wu army, the Chu army hurried back to Hanshui to deploy, and the two sides entered a confrontation. During the confrontation stage, The Chu army Zuo Sima made a relatively reasonable suggestion, that is, the main force under the command of Zi Chang stayed in the hanshui defense, and he himself led a partial division to detour to the rear of the Wu army in an attempt to cut off the Wu army's retreat. However, Zi Chang was afraid that the merits would be robbed, changed the battle plan that had been discussed and formulated, and attacked first, the Wu army under the leadership of Sun Wu deliberately showed weakness to lure the enemy to go deeper, and then defeated the main force of the Chu army in One fell swoop at Baiju, and then pursued five battles and five victories, and attacked the capital of the Chu state in only ten days.
In summary, although the battle of Wu Chu Baiju is very different in terms of the number of troops, if you zoom in on the perspective of the entire Wu-Chu struggle for hegemony, in fact, before the Battle of Baiju, the strength of wu has expanded sharply, not only has good international relations and many supporting allies. At the same time, he gained the strategic initiative through the Battle of the Chicken Father and six years of fatigue. Coupled with the chaos of the Chu state, the fatigue of the army, the low morale, and the continuous revolts in the country, the strength of the Chu army was far less powerful than it seemed. Coupled with the experience and ability of Sun Wu, Wu Zixu, and Wu Wanglu, the battle of Baiju with 30,000 Wu troops defeating 200,000 Chu troops is also understandable.