Chapter 19: The Consolidation of Duke Wen of Jin’s Hegemonic Status

With the decline of Qi’s hegemony and the internal turmoil that plagued Jin following Li Ji’s interference, the state of Chu, under the rule of King Cheng, grew increasingly prosperous and powerful. Most of the smaller states in the Central Plains—Zheng, Xu, Chen, Cai, Lu, Wei, Cao, and Song—either submitted to Chu or wavered between it and Jin, leaving Chu on the verge of establishing dominance over the region.

After Duke Wen of Jin ascended the throne, he stabilized his state, fostered economic growth, and granted his people respite. Furthermore, by intervening in the Rebellion of Prince Dai to protect the King and actively strengthening ties with Qin and Qi, he restored Jin’s status as a formidable power with ambitions of its own. Consequently, the situation Chong’er had once predicted while in exile—that Jin and Chu would eventually clash in the Central Plains—became inevitable.

Following the failure of Duke Xiang of Song to establish hegemony and his subsequent crushing defeat by Chu, Song was forced into submission. However, Duke Cheng of Song held a deep grudge against the Chu people for the death of his father, and, recalling the hospitality Duke Xiang had shown to the exiled Duke Wen, he decided to abandon Chu and align with Jin once the latter’s strength was restored. Enraged by this public betrayal, Chu allied with Zheng, Xu, Chen, and Cai to invade Song, eventually laying siege to its capital. Duke Cheng of Song dispatched Gongsun Gu to Jin to plead for urgent assistance.

Upon receiving the plea, Duke Wen consulted his ministers. Xian Zhen, a Jin official, advised: "Repaying Song’s past kindness, establishing Jin’s current prestige, and securing our future hegemony all depend on this single move." Hu Yan further proposed a strategy: "Chu has recently allied with Cao and formed marriage ties with Wei. To save Song, we need not confront the powerful Chu army directly. If we attack the smaller states of Cao and Wei, Chu will surely abandon the siege of Song to rescue them."

Recalling how Duke Gong of Cao had once rudely spied on him while he bathed during his exile, Duke Wen—who still harbored resentment—readily agreed. To prepare for the campaign, Jin expanded its military from two armies to three, selected its commanders, and, after a grand review at Beilu, set out.

After several setbacks and the conquest of Wei along the way, the Jin army besieged the capital of Cao. The city’s defenses were formidable, and the Jin troops suffered heavy losses. To demoralize them, the people of Cao hung the corpses of fallen Jin soldiers upon the city walls. Distressed by the sight of their dishonored comrades, the Jin army grew restless, a situation Duke Wen viewed with great concern. One advisor suggested, "Since they treat our dead with such indignity, we should camp by their ancestral tombs to disturb their peace."

Duke Wen followed this advice, moving the army near the ancestral burial grounds of Cao. Terrified by the threat to their ancestors, the people of Cao fell into a panic and quickly retrieved the corpses, burying them in coffins and returning them to the Jin camp. Seizing the opportunity created by this internal chaos, Duke Wen ordered an assault and successfully captured the capital.

Although Jin conquered Cao, Chu did not lift the siege on Song as predicted; instead, it intensified the attack. With Song on the brink of collapse, Duke Wen consulted Xian Zhen: "Song is pleading for help again. If we do not intervene, they will break with us and fully submit to Chu. But if we seek a compromise, Chu refuses. If we fight, Qi and Qin will not support us. What shall we do?"

Xian Zhen suggested: "Let the envoy from Song offer gifts to Qi and Qin, asking them to mediate. We shall keep the ruler of Cao captive and offer the lands of Cao and Wei to Song. Since Chu is allied with them, they will surely reject the peace proposal. Once Qi and Qin have accepted Song’s gifts and are provoked by Chu’s arrogance, will they not join us in war?" Duke Wen agreed and acted accordingly.

With Jin, Qi, and Qin now allied, Chu’s position became increasingly precarious. Sensing the shifting tides, King Cheng of Chu intended to withdraw and sent orders to his commander, Prime Minister Ziyu. However, Ziyu was arrogant and prideful; having once been criticized for lacking the ability to lead more than three hundred chariots, he refused to retreat. He sent word to the King, "I do not seek glory, but I must silence the petty men who doubt me." Angered by this insubordination, King Cheng provided Ziyu with only a small force and one hundred and eighty chariots.

Ziyu was not without talent. Before the battle, he sent Wan Chun to the Jin camp to negotiate: "If you restore the ruler of Wei and return the lands of Cao, I shall withdraw and lift the siege of Song." While Hu Yan wanted to refuse, Xian Zhen saw the trap: "If Chu claims to have settled the crises of these three states with a word, and we refuse, we will be seen as lacking in benevolence and propriety. Instead, let us secretly negotiate with Cao and Wei, offering them benefits, and then arrest Wan Chun to incite Chu. The blame for starting the war will then fall solely upon them." Duke Wen adopted this plan, and Cao and Wei duly severed their ties with Chu.

Enraged by this news, Ziyu ordered an attack, but the Jin army retreated instead of engaging. As the soldiers grew confused, Hu Yan explained: "Only an army with a just cause can prevail. Without Chu’s past support, our ruler would not be where he is today. While in exile, he promised that if they ever met in battle, Jin would retreat 'three stages.' We do this now to repay our debt. If we retreat and the Chu army remains aggressive, it is they who are the aggressors."

The Jin army retreated, and Ziyu pursued them until they reached Chengpu (modern-day Linpu, Shandong). There, the forces of Duke Cheng of Song, the Qi general Guo Guifu, and the Qin general Xiaoye Jin joined them. The Chu army encamped with their backs to the hills. Still hesitant due to his past debt to King Cheng, Duke Wen was encouraged by Hu Yan: "Fight! If we win, we achieve hegemony. If we lose, our state remains intact."

Ziyu then sent a challenge: "I invite the Prince to a game with his soldiers; he need only watch from his chariot!" Duke Wen replied with a formal appointment for battle the next morning: "I trouble the Minister to tell your masters: prepare your chariots, attend to your duties, and we shall meet at dawn!"

The next day, the largest battle of the Spring and Autumn period began. Duke Wen deployed seven hundred chariots north of the Shen region, ordering Xu Chen to lead the lower army against the forces of Chen and Cai. Ziyu commanded the Ruo’ao clan’s one hundred and eighty chariots in the center, with Zixi leading the left wing and Zishang the right, vowing to annihilate Jin.

The Jin army launched the first strike. Xu Chen covered his horses in tiger skins, leading a fierce charge against Chen and Cai. They fled, and the Chu right wing collapsed. To lure the enemy, Hu Mao set up two large banners to simulate a retreat, while Luan Zhi ordered his chariots to drag tree branches to create dust. Ziyu took the bait and pursued. Xian Zhen and Xi Zhen then led the center in a flanking maneuver, while Hu Mao and Hu Yan attacked the Chu left wing. The Chu left flank broke, leaving only Ziyu’s center to salvage what they could before fleeing back to Chu.

Although the defeat at Chengpu did not destroy the core of the Chu army, it shattered their plans for Northern expansion. Ziyu committed suicide in disgrace. From then on, Chu focused its efforts on the south, and Duke Wen’s hegemony was firmly established.

Following the battle, Duke Wen was not joyful but deeply troubled. When asked why, he sighed, "I have heard that only a sage can find peace after defeating an enemy. Ziyu still lives; who knows when he might return?" Soon after, news arrived that Ziyu had been forced to take his own life.

After the defeat, Ziyu’s center had remained largely intact, and he had retreated with the remnants of his forces. However, upon returning to Chu, King Cheng, furious at Ziyu’s reckless pursuit of battle, sent a messenger to question him: "If you return, how am I to answer the elders of Shen and Xi whose sons died under your command?" Realizing he had been abandoned by his King, Ziyu committed suicide. Hearing this, Duke Wen rejoiced: "I defeated their army abroad, and the King executed his commander at home. With the state weakened from within and without, I can finally rest easy."

Seeing that Chu was no longer an immediate threat, Duke Wen stationed his army at Hengyong (modern-day Yuanyang, Henan) and, assuming the role of hegemon, summoned the feudal lords. Seeing Jin’s recent victory, none dared to refuse, and even Chen, which had fought alongside Chu, attended the assembly.

Satisfied with his prestige, Duke Wen realized his status lacked the formal recognition of the Zhou royal court. He considered leading the lords to Luoyi to pay respects to King Xiang of Zhou, but fearing that a long journey might invite rebellion at home, he decided instead to build a palace at Jiantu and invite the King there to perform the rites of investiture.

Before the Battle of Chengpu, Chu’s influence had permeated the Central Plains, forcing even great states like Qi to submit. To the Zhou court and the states of the Central Plains, Duke Wen’s victory was a great service. Given the King’s waning power and Duke Wen’s past loyalty during the Rebellion of Prince Dai, King Xiang gladly accepted the invitation to reward the Jin army and its leader.

Zheng, which had served as a guide for the Chu army and had once rudely turned away the exiled Chong’er, now feared retribution. Desperate, they sent envoys to seek peace. Mindful of his long years in exile, Duke Wen did not hold a grudge and welcomed the alliance.

At Jiantu, Duke Wen presented his captives to King Xiang, including one hundred Chu chariots and one thousand infantry, demonstrating his loyalty. King Xiang received him with the highest honors and, through his ministers, officially invested Duke Wen as a "Houbo" (Overlord). This act formally recognized his status as the hegemon.

The King bestowed upon him ceremonial regalia, including grand chariots, ritual robes, red bows and arrows, black bows and arrows, fragrant wine for sacrifices, and three hundred royal guards. The ministers then empowered him to oversee the states and punish the disobedient: "The Son of Heaven tells his Uncle: Respectfully obey the royal commands, pacify the four corners, and correct the King’s errors." Duke Wen declined three times according to ritual before accepting, thus concluding the formal acknowledgement of his hegemony.

Soon after, King Xiang ordered a meeting of the lords at Jiantu to swear an oath: "Strive to support the royal house, do not infringe upon one another, and may the gods strike down those who break this oath!" This assembly not only prohibited unauthorized warfare but also provided Duke Wen with the "banner of loyalty" under which he could legitimately punish those who disobeyed the King’s commands, thereby cementing Jin’s supremacy for years to come.