Wei Yan
Wei Yan was from Yiyang Commandery (), which covered parts of present-day Nanyang in southern Henan and parts of northern Hubei. He started his career as a foot soldier under the warlord Liu Bei, probably sometime between 209 and 211 when Liu Bei was in southern Jing Province (covering present-day Hubei and Hunan). Around 212, he followed Liu Bei into Yi Province (covering present-day Sichuan and Chongqing) and served Liu Bei as a personal retainer in a war against Liu Zhang, the Governor of Yi Province (益州牧). Huang Zhong and Wei Yan scored many military exploits during the capture of Guanghan County. Thus, Wei Yan promoted to full general. Although the campaign met early success with the quick death of Gao Pei and Yang Huai and the later occupation of the passes followed by the defeat of Liu Zhang's reinforcement at Fu County. Pang Tong was killed during the siege of Luo castle and the It became a prolonged one. One year later, Wei Yan and Liu Bei finally captured Luocheng, then surrounded and occupied Chengdu together with Zhuge Liang, Zhang Fei along with others. Thus, around summer 214, Liu Bei seized control of Yi Province from Liu Zhang. As Wei Yan has made several contributions in the campaign of Yi, Liu Bei promoted him to the rank of General of Ivory Gate (). In 219, Wei Yan participated in Liu Bei campaign against his rival Cao Cao in the Hanzhong Campaign. After Liu Bei captured Hanzhong, Liu Bei asked his subjects to nominate one of his generals to remain behind and guard Hanzhong. His subjects nominated Zhang Fei, who also strongly believed that he would most likely be chosen. However, much to everyone's surprise, Liu Bei chose Wei Yan instead and appointed him as General Who Guards Distant Lands () and acting Administrator of Hanzhong (). When Liu Bei asked Wei Yan in front of everyone how would he perform his duty, the latter confidently replied: 
During his tenure, Wei Yan explained to Liu Bei that he borrowed a strategy which were called the "double gates" (重门之计). This strategy adopted from the ancient text "I Ching"described it as a particularly designed fortifications which laid numerous military garrisons surrounding the outskirt and trail exits linking to Hanzhong. Following the end of the Eastern Han dynasty and the start of the Three Kingdoms period in 220, Liu Bei declared himself emperor in 221 and established the state of Shu Han (or Shu) to challenge the legitimacy of the Cao Wei (or Wei) state established by Cao Cao's successor, Cao Pi, to replace the Eastern Han dynasty. Liu Bei further promoted Wei Yan to General Who Guards the North () after his coronation. After Liu Bei died in 223, his son Liu Shan succeeded him as the emperor of Shu. In the same year, Liu Shan enfeoffed Wei Yan as a Marquis of a Chief Village (). In 227, Zhuge Liang, the Imperial Chancellor of Shu, mobilised the Shu military and gathered troops in Hanzhong Commandery in preparation for a large-scale invasion of Shu's rival state, Cao Wei (or Wei), where he put Wei Yan in charge of the vanguard division and appointed him as acting Major under the Imperial Chancellor () and acting Inspector of Liang Province (). During this campaign, Wei Yan always requested to lead a separate detachment of 10,000 troops, take a different route and rendezvous with the Shu main army at Tong Pass (潼關; in present-day Tongguan County, Shaanxi). Wei Yan argued that The valley and the people in it has sufficient food supply which can support the operation at least for a week. However, Zhuge Liang rejected the plan because he thought that it was too risky, which prompted Wei Yan to scold Zhuge Liang as a coward and complained that his talent was not put to good use. When Chen Shou compiled the unofficial works on the history of Shu to write the "Sanguozhi", he only mentioned that Wei Yan suggested to Zhuge Liang to split the Shu army into two, and the two forces would take two different routes and rendezvous at Tong Pass.
Later in 230, during the Ziwu Campaign, Wei Yan led some troops towards Yangxi (陽谿; southwest of present-day Wushan County, Gansu) and engaged the Wei forces led by and Guo Huai and Fei Yao, where Wei Yan managed to inflict a heavy defeat to them. Also, during the same year, he assisted another Shu general Wu Yi, both of them were ordered to attack Nan'an Commandery (南安郡; southeast of present-day Longxi County, Gansu) where they scored another victory against Wei's army led by Fei Yao. During the fourth campaign in 231, Wei Yan was also involved in the Battle of Mount Qi when he together with the Shu generals Gao Xiang and Wu Ban, scored a major victory against the Wei army led by Sima Yi, where they killed 3,000 Wei soldiers and seized 5,000 sets of armour and 3,100 crossbows. Sima Yi was forced to retreat back to his camp. Zhang He, a veteran Wei general was also killed in battle during this conflict. As a reward for his contributions, the Shu government promoted Wei Yan to Vanguard Military Adviser () and Senior General Who Attacks the West (), and elevated him from a village marquis to a county marquis under the title "Marquis of Nanzheng" (). In 234, Zhuge Liang launched the fifth Shu invasion of Wei, with Wei Yan leading the Shu vanguard force as one of his commanding officer, Wei Yan reportedly had a dream that on the top of his head would grow a horn, he asked the meaning of this to the dream diviner Zhao Zhi (趙直). Zhao Zhi lied to him and said: 
After he left, he revealed to someone that the word "horn" (角) is composed of a "knife" (刀) with "use" (用) bellow it, which mean dreaming of "using knife" atop one person head and were considered as extremely ominous omen. Later, in the encampment Wei Yan had a quarrel with Yang Yi, Zhuge Liang's chief clerk, as Wei Yan was extremely resentful of Yang Yi. Whenever they got into heated quarrels, Wei Yan often drew his sword and brandished it in front of Yang Yi who sobbed as tears rolled down his cheeks; which prompted Fei Yi then to stepped in to stop them from fighting and managed to keep them under control until Zhuge Liang's death. Zhuge Liang was upset by the lack of harmony between Wei Yan and Yang Yi, but was unwilling to side with either of them because he appreciated the talents of both men. When Zhuge Liang became critically ill during the invasion, he gave secret orders to Yang Yi, Fei Yi and Jiang Wei to lead the army back to Shu after his death, with Wei Yan in charge of the rearguard and Jiang Wei to follow behind, and being instructed If Wei Yan refused to follow the order, they were to retreat without him. When Zhuge Liang died, news of his death were kept secret. Yang Yi sent Fei Yi to meet Wei Yan and assess his intentions. Wei Yan told Fei Yi: 
Wei Yan then asked Fei Yi to assist him in making arrangements for part of the Shu army to remain behind and continue with the campaign, while the rest would retreat back to Shu. Fei Yi pretended to write a letter, signed by both of them, and told Wei Yan that he would read out the letter to all the officers about the new arrangements, where he lied by telling Wei Yan that he will go back and explain Wei Yan answer to Yang Yi. Wei Yan then let Fei Yi leave, but he immediately regretted his decision and went after Fei Yi, although Wei Yan could not catch up Fei Yi in time. He then sent his subordinate to meet Yang Yi and the others, but was shocked to discover that all units were preparing to retreat in accordance with Zhuge Liang's final orders. Wei Yan wanted to continue the battle even though Zhuge Liang had died, so he became furious when he heard of the retreat. He intended to block the Shu forces from retreating, so he led his force towards the south – ahead of the main army under Yang Yi's command – and sealed the return route by destroying the gallery roads leading back to Shu. Wei Yan and Yang Yi separately wrote memorials to the Shu imperial court to accuse each other, which both memorials arrived in Chengdu on the same day. The Shu emperor Liu Shan asked the ministers Dong Yun and Jiang Wan for their opinions. Both of them sided with Yang Yi and felt that Wei Yan's actions were suspicious. In the meantime, Yang Yi ordered his men to cut down trees to rebuild the gallery roads, and his troops marched day and night to catch up with Wei Yan. Wei Yan arrived at the southern valley first and ordered his soldiers to attack Yang Yi. Yang Yi sent Wang Ping to resist Wei Yan. Wang Ping shouted at Wei Yan: 
As Wei Yan was left with only his son(s) and a few followers, They fled towards Hanzhong Commandery, Yang Yi ordered Ma Dai to give chase and caught up with Wei Yan. Ma Dai killed Wei Yan, brought his head back, and threw it in front of Yang Yi. Yang Yi trampled on Wei Yan's decapitated head and said: 
Thus, the family members and close relatives of Wei Yan were also executed. Before Wei Yan's death, Jiang Wan had led the imperial guards from Chengdu to deal with what appeared to be a mutiny by Wei Yan. They had travelled for about 10 "li" (about three miles) when they received news of Wei Yan's death; they then turned back and returned to Chengdu. Wei Yan was known to treat his soldiers well and for his bravery with valor that surpassed others, although he was also boastful of his talents hence his peers tended to avoid him. Sun Quan, the ruler of Wu and another contemporary figure of three kingdoms era, has remarked that the moment Zhuge Liang passed away, Wei Yan will be proven unreliable. Chen Shou, who wrote Wei Yan's biography in the "Sanguozhi", analysed Wei Yan's death as such:
Administrator of Hanzhong
He was later appointed as the Administrator of Hanzhong Commandery and as an Area Commander in 219.