Cai Lin

Historical Record

Cai Lin was a general of Eastern Wu, whose life and deeds are seen mainly during Zhuge Ke's northern campaign. According to the historical record, after the Battle of Dongxing, Zhuge Ke intended to press the victory by marching on Huainan, hoping to expand his gains and seize population. However, his generals objected to this strategy, holding that pushing deep into enemy territory would exhaust the troops for little gain, and advising that it would be better instead to besiege Xincheng. Zhuge Ke adopted this advice and turned his army back to besiege Xincheng. Yet the siege dragged on for several months, and Xincheng held firm and could not be taken. During this time, the Wu soldiers, worn out from prolonged fighting and amid sweltering heat and foul drinking water, fell prey to an epidemic spreading through the army, with symptoms of diarrhea and swelling, and many died of illness^[1].

The camp officers reported the daily death toll, but Zhuge Ke believed they were exaggerating to shake the army's morale, and even threatened to behead those who reported illness. As a result, no one in the army any longer dared to report the true situation. Zhuge Ke knew in his heart that this decision had been a blunder, yet was ashamed that the city remained long untaken, and his anger showed plainly. Against this backdrop, the general Zhu Yi once raised objections to certain of Zhuge Ke's decisions, and in his fury Zhuge Ke immediately stripped him of his military authority. The Commandant Cai Lin also repeatedly presented military strategies to Zhuge Ke, but his advice was never adopted^[1].

In the end, with the Wu army's morale low and the epidemic spreading, Cai Lin chose to gallop over to Wei and surrender to Cao Wei. Learning that the Wu army was already exhausted and plague-ridden, the Wei army seized the opportunity to send reinforcements. Seeing this, Zhuge Ke was forced to withdraw. On the retreat, the Wu army, beset by wounds and illness, saw its soldiers scattered—some falling dead in pits and gullies, others captured by the Wei army. The surviving officers and men, still vivid in their memory of the bitter ordeal of this campaign, were filled with resentment and grief. Zhuge Ke, however, showed himself perfectly composed about it, lingering by the river isles for a month after the withdrawal and even planning to establish military farms at Xunyang. Only after repeated urgent edicts from the court did he slowly lead the army back. The failure of this campaign and Zhuge Ke's various behaviors left the people of Wu bitterly disappointed and full of complaint^[1]. Cai Lin's defection was indeed an epitome of the failure of this northern campaign, and also reflected the many problems in Zhuge Ke's military command and his handling of human relationships.

In the Novel

In Romance of the Three Kingdoms, Cai Lin's image echoes the historical record, but the episodes are more dramatized and concrete. In the novel, while besieging Xincheng, Zhuge Ke was deceived by a delaying ruse from the Wei general Zhang Te. Zhang Te feigned a request to surrender, leading Zhuge Ke to believe it and halt the assault^[2]. However, Zhang Te used this time to repair the city's defenses, then mounted the wall and reviled the Wu army, enraging Zhuge Ke. In a great rage, Zhuge Ke pressed the attack again, but was struck in the forehead by a stray arrow beneath the wall, tumbling from his horse and seriously wounded. After this the Wu army's morale fell still lower, and amid the sweltering weather an epidemic raged through the army, with many of the officers and men falling ill.

After his wound had somewhat healed, Zhuge Ke still insisted on pressing the assault. When a camp officer reported to him that the army was full of sick men who could fight no more, Zhuge Ke angrily rebuked him and threatened to behead those who reported illness. As a result, countless men deserted^[2]. It was against this backdrop that the novel explicitly states, "Suddenly it was reported that the commander Cai Lin had led his own troops over to Wei"^[2]. Alarmed at the news, Zhuge Ke personally rode out to inspect the camps, and indeed found the soldiers sallow and swollen, faces full of illness—only then was he forced to rein in the troops and return to Wu. Learning that the Wu army had withdrawn, the Wei general Guanqiu Jian thereupon led a great army in pursuit, dealing the Wu army a crushing defeat.

The novel further depicts Zhuge Ke's circumstances after returning to Wu. Ashamed of his defeat, he feigned illness and did not attend court. The Wu sovereign Sun Liang personally came to visit, and the civil and military officials likewise came in succession to pay their respects. Fearing that everyone would discuss his responsibility for the defeat, Zhuge Ke began to seek out the faults of officials, banishing the lesser offenders to the frontier and beheading the graver ones as a public warning, so that the whole court was struck with fear. He also appointed his confidants Zhang Yue and Zhu En to command the imperial guards, to consolidate his own power^[2]. The novel's depiction of Cai Lin's defection to Wei not only preserves the core event of historical fact but, through Zhuge Ke's personal experiences and psychological activity, reinforces his image as stubborn, self-willed, and given to slaughtering the innocent, thereby giving fuller literary grounding to the plausibility of Cai Lin's defection.

Key Relationships

* Zhuge Ke (betrayed_by): Cai Lin repeatedly presented military strategies to Zhuge Ke, but his advice was never adopted^[1]. During Zhuge Ke's northern campaign against Xincheng, his stubbornness and disregard for his soldiers led to epidemic and low morale in the army. In the end, Cai Lin chose to abandon Zhuge Ke and surrender to Cao Wei^[1]. In the novel, Cai Lin's defection to Wei occurs directly after Zhuge Ke, frustrated by the unfavorable course of the war, slaughtered camp officers—further highlighting Zhuge Ke's misjudgment and his being deserted by all^[2].
* Cao Wei (defected_to): As the morale of the Eastern Wu army fell and the epidemic spread, Cai Lin galloped over to Wei and surrendered to Cao Wei^[1]. His surrender provided Cao Wei with important intelligence on the internal state of the Wu army, prompting the Wei army to seize the opportunity to send troops in pursuit, so that Zhuge Ke's northern campaign ended in crushing defeat. In the novel, after Cai Lin defected to Wei, the Wei general Guanqiu Jian learned of the Wu army's withdrawal and thereupon led a great army to fall upon them, routing the Wu army^[2].
* Eastern Wu (defected_from): Cai Lin was originally a Commandant of Eastern Wu. During Zhuge Ke's northern campaign, dissatisfied with Zhuge Ke's decisions and with the unfavorable course of the war, he ultimately chose to betray Eastern Wu and turn to Cao Wei^[1]. His defection was an important link in the failure of this Wu northern campaign, and also reflected the crisis Eastern Wu faced internally during Zhuge Ke's autocratic rule.

Iconic Scenes

* Remonstrance during the siege of Xincheng and defection to Wei: This is the most iconic scene of Cai Lin's life. During Zhuge Ke's siege of Xincheng, the Wu army's morale fell amid the failure to take the city and the spread of epidemic. As Commandant, Cai Lin repeatedly offered military advice to Zhuge Ke, but it was never adopted^[1]. Against the backdrop of Zhuge Ke acting willfully and even threatening to behead camp officers who reported illness, Cai Lin ultimately chose to gallop over to Wei and surrender to Cao Wei^[1]. This act was not only the turning point of his personal fate but also directly brought about the Wei army's intervention, hastening the failure of Zhuge Ke's northern campaign. In the novel, Cai Lin's defection to Wei occurs amid the extreme predicament of Zhuge Ke being wounded by an arrow, the epidemic spreading through the army, and countless soldiers deserting, making his defection all the more dramatic and inevitable^[2].
* The Wei army pressing the pursuit: After defecting to Wei, Cai Lin informed Cao Wei of the Wu army's exhaustion and plight. Upon learning this important intelligence, the Wei army immediately sent reinforcements and launched a pursuit as Zhuge Ke withdrew, routing the Wu army^[1]. In the novel, Cai Lin's report of his defection to Wei directly prompted Guanqiu Jian to "raise all his great army and fall upon them from behind," leading to "the Wu troops being crushingly defeated"^[2]. This scene highlights the real military impact of Cai Lin's surrender and makes him a key factor in the failure of Zhuge Ke's northern campaign.