1. Xiao Yu, courtesy name Shiwen, posthumously known as Duke Zhenbian of Song, was an imperial prince of the Western Liang dynasty who later became an official under the Sui and Tang dynasties.

1. Xiao Yu, courtesy name Shiwen, posthumously known as Duke Zhenbian of Song, was an imperial prince of the Western Liang dynasty who later became an official under the Sui and Tang dynasties.
Xiao Yu served as a chancellor during the reigns of the emperors Gaozu and Taizong in the early Tang dynasty.
Xiao Yu was born in 575, during the reign of his father Xiao Kui, Emperor Ming of Western Liang, who claimed the throne of Liang dynasty but whose territory, known in history as the Western Liang, was limited to a small amount of territory around his capital Jiangling.
Xiao Yu followed her to the Sui capital Chang'an, and he became known for studiousness and proper actions there.
Xiao Yu was particularly attentive in studying Buddhist sutras and became a devout Buddhist, spending much of his time discussing Buddhism with monks.
Western Liang was at its end, although its imperial clan members, including Xiao Yu, continued to be treated well by Emperor Wen.
In 600, after Yang Guang displaced his older brother Yang Yong as crown prince, Xiao Yu continued to serve on Yang Guang's staff, as a guard commander.
When, at one point, Xiao Yu became suddenly ill, he ordered that no medical treatment be carried out, believing that this would be a good time for him to be relieved from governmental service.
However, when Empress Xiao Yu heard this, she visited him and rebuked him, pointing out that this kind of behavior might in fact bring punishment from Emperor Yang.
Xiao Yu, who had accompanied the emperor, suggested that messengers be sent to Princess Yicheng, as Turkish customs dictated that the khan's wife be in charge of military matters at home while he was away.
Just because they did not do so immediately, Xiao Yu was frightened; this is unforgivable.
When Xiao Yu got to Hechi Commandery, there were agrarian rebels in the mountains, numbering over 10,000, whom the commandery government was unable to control.
Xiao Yu reorganized the commandery militia and attacked them, forcing them to surrender.
Subsequently, when Xue Ju rebelled at Jincheng Commandery and attacked east, Xiao Yu blocked Xue's path, and Xue was not able to advance further at that point.
Li Yuan assumed power as regent, and he wrote to Xiao Yu, requesting that Xiao submit.
Xiao Yu agreed, and was made the minister of census and created the Duke of Song.
In spring 618, during an abortive campaign where Li Yuan sent his sons Li Jiancheng and Li Shimin with an army to the eastern capital Luoyang to try to get Sui officials there to submit, Xiao Yu served on Li Shimin's staff.
Xiao Yu made Xiao Yu Neishi Ling, the head of the legislative bureau of the government and a post considered one for a chancellor, and he entrusted Xiao with some of the most important matters of state.
Later, after the legislative bureau was renamed Zhongshu Sheng in 620, Xiao Yu remained its head with the new title of Zhongshu Ling.
In 621, he was similarly put in charge, along with Pei and Chen Shuda, of interrogating Li Zhognwen the Duke of Zhenxiang, who was charged with treason, and while Xiao Yu's recommendations were unclear, Li Zhongwen was executed.
At times, when Emperor Gaozu issued edicts, he wanted the legislative bureau to promulgate them quickly, but Xiao Yu did not do so.
When Emperor Gaozu rebuked him, Xiao Yu pointed out that during Emperor Yang's reign, the edicts were issued quickly, and while officials had valid reservations, they did not dare to speak against it.
Xiao Yu wanted the edicts to be issued only after greater examination, and so was not issuing them as quickly.
Meanwhile, as Xiao Yu's property was initially seized by Emperor Gaozu when he first entered Chang'an to be awarded to the military officers with accomplishments, Emperor Gaozu returned the property to Xiao Yu.
Xiao Yu divided the property and distributed it to his clan members, only keeping the family shrine so that he could sacrifice to the ancestors.
Xiao Yu was unable to prevail over Fu in the debate, and Emperor Gaozu issued an edict severely limiting the number of Buddhist temples, although the edict did not appear to be seriously carried out.
Xiao Yu submitted a secret petition to Emperor Gaozu accusing Li Jiancheng and another brother, Li Yuanji the Prince of Qi, who supported Li Jiancheng, of committing adultery with Emperor Gaozu's concubines and plotting to kill him.
Later that year, Emperor Taizong discussed attacking Eastern Tujue, which Xiao Yu favored, but Zhangsun Wuji opposed, and therefore Emperor Taizong did not carry out the attack.
Around the new year 628, Xiao Yu was again removed from his position, for reasons not stated in history, although in spring 630 he was made a de facto chancellor as imperial censor.
Meanwhile, Xiao Yu continued to be arrogant and harsh and was again not getting along with the other chancellors.
Xiao Yu was made the examiner of Henan Circuit, but on his mission, he overly punished an official who did not listen to the people under him about their suffering by putting him in a block, causing that official's death.
Xiao Yu wrote a poem to Xiao Yu, including these two lines:.
Soon thereafter, Emperor Taizong, believing that Li Tai had played a role in Li Chengqian's downfall, created another son, Li Zhi the Prince of Jin, crown prince, instead of Li Tai, and Xiao Yu was made a senior advisor of the new crown prince.
Xiao Yu was given a newly created title for a de facto chancellor as well, Tong Zhongshu Menxia Sanpin.
In 646, Xiao Yu was again in discord with the other chancellors, going as far as accusing Fang of factionalism bordering on treason.
Xiao Yu demoted Xiao to the post of prefect of Shang Prefecture, but cancelled Xiao's title as Duke of Song.
In 647 Emperor Taizong recalled Xiao Yu to be an imperial advisor and restored his title of Duke of Song.
In 648, while accompanying Emperor Taizong at Yuhua Palace, Xiao Yu grew ill and died.