Liu Shan

During the early years of his reign, Liu Shan was not an unwise ruler. While Zhuge Liang was alive, Liu Shan treated him as a father figure, allowing Zhuge to handle all state affairs. Zhuge Liang recommended many trusted officials, including Fei Yi, Dong Yun, Guo Youzhi and Xiang Chong into key positions. Under Zhuge Liang's advice, Liu Shan entered into an alliance with the state of Eastern Wu, helping both states to survive against the much larger state of Cao Wei. During Zhuge Liang's regency, the government was largely efficient and not corrupt, allowing the relatively small state of Shu to prepare itself for military campaigns.

In 223, Liu Shan married Zhang Fei's daughter, Empress Zhang.

In the aftermath of Liu Bei's death, the southern Nanman tribes had peeled away from Shu dominion. In 225, Zhuge Liang headed south and was able to, by both military victories and persuasion, reintegrate the southern region into the empire. For the rest of Zhuge Liang's regency, the southern Nanman people would be key contributors to Shu's campaigns against Wei.

Starting in 227, Zhuge Liang launched his five Northern Expeditions against Wei, but all except one were military failures (albeit not military disasters) in that his forces ran out of food before they were able to inflict significant damage on Wei and therefore were forced to withdraw. It was during one of Zhuge Liang's campaigns that the only real political crisis during Zhuge's regency would occur. In 231, unable to supply the troops sufficiently, Zhuge Liang's co-regent Li Yan forged an edict by Liu Shan, ordering Zhuge Liang to retreat. When Zhuge Liang discovered this, he recommended that Li Yan be removed from his office and put under house arrest, and Liu Shan accepted the recommendation.

In 234, while Zhuge Liang was on his final campaign against Wei, he grew seriously ill. Hearing about Zhuge's illness, Liu Shan sent his secretary Li Fu (李福) to the front line to visit Zhuge Liang and to request Zhuge to leave instructions on important state matters. Among other things, Zhuge Liang recommended that Jiang Wan succeed him, and that Fei Yi succeed Jiang Wan. Zhuge Liang refused to answer Li Fu's next question — who should succeed Fei Yi. Zhuge Liang died soon thereafter. Liu Shan followed Zhuge's instructions and installed Jiang Wan as the new regent.

Jiang Wan was a capable administrator, and he continued Zhuge Liang's domestic policies, leaving the government largely efficient. He was also known for his tolerance of dissension and his humility. Not having much military aptitude, however, he soon abandoned Zhuge Liang's aggressive foreign policy towards Wei, and indeed in 241 withdrew most of the troops from the important border city of Hanzhong to Fu County (涪縣; in present-day Mianyang, Sichuan). From that point on, Shu was generally in a defensive posture and no longer posed a threat to Wei. (This was in fact misinterpreted by many Wu officials as a sign that Shu was abandoning the alliance and entering into a treaty with Wei, but was correctly read by Wu's emperor Sun Quan as merely a sign of weakness, not an abandonment of the alliance.)

In 237, Empress Zhang died. That year, Liu Shan took her younger sister as a consort, and in 238 created her empress. Her title remained the same as her sister, Empress Zhang.

In 243, Jiang Wan grew ill and transferred most of his authority to Fei Yi and Fei's assistant Dong Yun. In 244, when Wei's regent Cao Shuang attacked Hanzhong, it was Fei Yi who led the troops against Cao Shuang and dealt Wei a major defeat in the Battle of Xingshi. Jiang Wan, however, remained influential until his death in 245. Soon after Jiang Wan's death, Dong Yun also died — allowing the eunuch Huang Hao, a favourite of Liu Shan's, whose power Dong Yun had curbed, to start aggrandising his power. Huang Hao was viewed as corrupt and highly manipulative in domestic matters, and the governmental efficiency that was achieved during Zhuge Liang's and Jiang Wan's regencies began to deteriorate.

After Jiang Wan and Dong Yun's deaths, Liu Shan named Jiang Wei as Fei Yi's assistant, but both were largely involved only in military matters, as Liu Shan gradually became more self-assertive in non-military matters. It was also around this time that he became more interested in touring the countryside and increasing the use of luxury items, both of which added stress on the treasury, albeit not cripplingly so. Jiang Wei was interested in resuming Zhuge Liang's policies of attacking Wei aggressively, a strategy that Fei Yi partially agreed with — as he allowed Jiang Wei to make raids on Wei's borders, but never gave him a large number of troops, reasoning that Shu was in no position for a major military confrontation with Wei.

In 253, Fei Yi was assassinated by the general Guo Xun (郭循) -- a former Wei general who had been forced to surrender but who secretly maintained his loyalty to Wei. Fei Yi's death left Jiang Wei as the de facto regent, but with a power vacuum in domestic affairs, as Jiang Wei continued to be on the borders, conducting campaigns against Wei. Huang Hao's influence increased greatly as a result.

After Fei Yi's death, Jiang Wei assumed command of Shu's troops and began a number of campaigns against Wei—but while they were troubling to the Wei regents Sima Shi and Sima Zhao, the attacks largely inflicted no real damage against Wei, as Jiang Wei's campaigns were plagued by one problem that had plagued Zhuge Liang's -- the lack of adequate food supply—and largely had to be terminated after a short duration. These campaigns instead had a detrimental effect on Shu, whose government no longer had the efficiency that it had during Zhuge Liang's and Jiang Wan's regencies, and therefore was unable to cope with the drain of resources that Jiang Wei's campaigns were having.

In 253, Jiang Wei made a coordinated attack on Wei, along with Wu's regent Zhuge Ke, but was eventually forced to withdraw after his troops ran out of food supplies — allowing Sima Shi to concentrate against Zhuge Ke, dealing Wu forces a devastating defeat that eventually caused so much resentment that Zhuge Ke was assassinated. This was the last of the coordinated attacks by Shu and Wu on Wei in the duration of the Shu-Wu alliance.

In 255, on one of Jiang Wei's campaigns, he dealt Wei forces a major defeat in the Battle of Didao, nearly capturing the important Wei border city Didao, but in 256, as he tried to again confront the Wei forces, he was instead dealt a defeat by Deng Ai, and this was a fairly devastating loss that left Jiang Wei with a weakened standing with the people. Many officials now openly questioned Jiang Wei's strategy, but Liu Shan took no actions to stop Jiang. Further, in 259, under Jiang Wei's suggestion, Liu Shan approved a plan where the main troops were withdrawn from major border cities to try to induce a Wei attack, with troops positioned in such a way as to intend a trapping of the Wei troops — a strategy that would be used several years later, in 263, when Wei did attack, but which would prove to be a failure.

By 261, Huang Hao's power appeared paramount. Among the key domestic officials, only Dong Jue and Zhuge Liang's son Zhuge Zhan were able to maintain their posts without flattering Huang Hao. In 262, Huang Hao would in fact try to remove Jiang Wei and replace him with his friend Yan Yu (閻宇). Upon hearing this, Jiang Wei advised Liu Shan to execute Huang Hao, but the emperor denied the request, saying that the eunuch was but a servant who ran errands. Fearing retaliation, Jiang Wei left Chengdu to garrison troops at Tazhong (沓中; northwest of present-day Zhugqu County, Gansu).

According to the Wu ambassador Xue Xu, who visited Shu in 261 at the order of the Wu emperor Sun Xiu, the status that Shu was in at this point was:

The emperor is incompetent and does not know his errors; his subordinates just try to get by without causing trouble for themselves. When I was visiting them, I heard no honest words, and when I visited their countryside, the people looked hungry. I have heard of a story of swallows and sparrows making nests on top of mansions and being content, believing that it was the safest place, not realising that the haystack and the support beams were on fire and that disaster was about to come. This might be what they are like.

In 262, aggravated by Jiang Wei's constant attacks, Wei's regent Sima Zhao planned to carry out a major campaign to terminate the Shu threat once and for all. Upon hearing rumours of this plan, Jiang Wei submitted a request to Liu Shan, warning him about the mustering of Wei troops under the generals Deng Ai, Zhuge Xu, and Zhong Hui near the border. However, Huang Hao persuaded Liu Shan with fortunetelling to take no action on Jiang Wei's requests for war preparations.

In 263, Sima Zhao launched his attacks, led by Deng Ai, Zhuge Xu, and Zhong Hui. Liu Shan followed Jiang Wei's previous plans and ordered the border troops to withdraw and prepare to trap Wei forces, rather than to confront them directly. The plan, however, had a fatal flaw — it assumed that Wei forces would siege the border cities, which, instead, Deng Ai and Zhong Hui ignored, and they advanced instead on Yang'an Pass (陽安關; in present-day Hanzhong, Shaanxi), capturing it. Jiang Wei was able to meet their troops and initially repel them, but Deng Ai led his army through a treacherous mountain pass and deep into Shu territory. There he launched a surprise attack on Jiangyou (江油; in present-day Mianyang, Sichuan). After defeating Zhuge Zhan there, Deng Ai had virtually no Shu troops left between his army and the Shu capital Chengdu. Faced with the prospect of defending Chengdu against Deng Ai's troops with no defences, Liu Shan took the advice of Secretary Qiao Zhou and promptly surrendered. While the surrender was criticised by many, the historian Wang Yin (王隱), in his Records of Shu (蜀記), described the move as a policy that placed the welfare of the people on top.

In 264, Zhong Hui would carry out an attempt to seize power — which Jiang Wei, who had surrendered to Zhong Hui, tried to take advantage of to revive Shu. He advised Zhong Hui to falsely accuse Deng Ai of treason and arrest him, and, with their combined troops, rebel against Sima Zhao. Zhong Hui did so, and Jiang Wei planned to next kill Zhong Hui and his followers, and then redeclare Shu's independence under emperor Liu Shan, and had in fact written to Liu Shan to inform him of those plans. However, Zhong Hui's troops rebelled against him, and both Jiang Wei and Zhong Hui were killed in battle. Liu Shan himself was not harmed in the disturbance, although his crown prince Liu Xuan was killed in the confusion.

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