Emperor Hui of Han

Liu Ying's childhood is not completely clear. What is known is that he was not his father Liu Bang's oldest son—that would be Liu Fei, who would later be made the Prince of Qi. However, Liu Ying was considered to be the proper heir because his mother, the later Empress Lü, was Liu Bang's wife, while Liu Fei's mother was either a concubine or a mistress.

What is also known is that during Chu–Han Contention, when Liu Bang fought a five-year war with Xiang Yu for supremacy over the Chinese world, his mother, his sister, and he did not initially follow his father to the Principality of Han (modern Sichuan, Chongqing, and southern Shaanxi); rather, they stayed in his father's home territory, perhaps in his home town of Pei (沛縣, in modern Xuzhou, Jiangsu) deep in Xiang's Principality of Western Chu, presumably with his grandfather Liu Zhijia.

In 205 BC, Liu Bang appeared to be near total victory, having captured Xiang's capital of Pengcheng. How his family received this news was unclear, but a few months later, when Xiang responded and crushed Liu's forces, Liu fled and, in his flight, attempted to pass through his home town to take his family with him. He was able to find his children and carry them along with him, but his father and wife were captured by Xiang's forces and kept as hostages—and would not be returned to him until Liu and Xiang temporarily made peace in 203 BC. The then-very young Liu Ying must have then spent these days not knowing what the eventual fate of his grandfather and mother would be.

After Liu Bang's victory and self-declaration as the emperor (later known as Emperor Gao), thus establishing the Han Dynasty, in 202 BC, he made his wife empress and Liu Ying, as his proper heir, crown prince. Under the title of Ying Taizi ("Crown Prince Ying"), he was considered to be kind and tolerant, characteristics that Emperor Gao did not like. Rather, he favored his young son Liu Ruyi, whom he considered to be more like him and whose mother, Consort Qi, was his favorite concubine. With the support of the officials, however, Prince Ying's status as heir survived despite Consort Qi's machinations.

As crown prince, Prince Ying, along with his mother, would be the ones who would rule on important matters at the capital in his father's absence during various campaigns. When Ying Bu rebelled in 196 BC, Emperor Gao was ill and considered sending Prince Ying as the commander of the forces against Ying Bu rather than campaigning himself, but at the suggestion of Empress Lü (who averred that the generals, who were generally Emperor Gao's old friends, might not fully obey the young prince), went on the campaign himself. Prince Ying was instead put in charge of home territories around the capital Chang'an, assisted by Confucian scholar Shusun Tong (叔孫通) and strategist Zhang Liang (張良). He appeared to carry out the tasks competently but without distinction.

Prince Ying succeeded to the throne of Han when his father died in 195 BC from complications of an arrow wound suffered during the campaign against Ying Bu.

Anling (安陵), the tomb of Emperor Hui, in Xianyang, Shaanxi

Immediately upon Prince Ying's ascension to the throne as Emperor Hui, Empress Lü, now empress dowager, became the effective lead figure in his administration. She wanted to carry out a plot of revenge against Consort Qi and her son Ruyi. She first arrested Consort Qi and put her in prison garb (shaved head, confined by stock, and wearing red clothes). She then summoned Liu Ruyi to the capital—an attempt that was initially resisted by Ruyi's chief of staff Zhou Chang (周昌), whom she respected because he was one of the officials who insisted on Liu Ying being the rightful heir. Instead of directly moving against Zhou and Liu Ruyi, though, Lü circumvented Zhou by first summoning him to the capital, and then summoning Liu Ruyi.

Emperor Hui tried to save Liu Ruyi's life. Before Liu Ruyi could get to the capital, Emperor Hui intercepted his young brother at Bashang (霸上, in modern Xi'an) and received Liu Ruyi into his palace, and they dined together and slept together. Empress Dowager Lü wanted to kill Liu Ruyi, but was afraid that any attempt might also harm her own son, and therefore could not carry out her plot for several months.

Empress Dowager Lü got her chance in winter 195 BC. One morning, Emperor Hui was out hunting and wanted to take Liu Ruyi with him. The young prince was then only 12 years old and refused to get up from bed, and Emperor Hui left for the hunt on his own. Empress Dowager Lü heard this and immediately sent an assassin into the emperor's palace to force poisoned wine down the prince's throat. By the time that Emperor Hui returned, his brother was dead. She then had Consort Qi's eyes gouged out, made her ears deaf, drugged her to make her unable to speak and had her arms and legs cut off. The mutilated woman was thrown to a toilet and fed and kept alive in a pig's bin and was called the "人彘", meaning literally the "human swine". (She would die from the torture.) When Emperor Hui saw his father's favorite and the mother of his beloved little brother in such a condition, he cried out loud and became ill for about a year, complaining to his mother that he felt that he could not govern the empire, given that he was the son of someone like her who has done such inhuman deed. From that point on, Emperor Hui indulged himself with wine and women and no longer made key governing decisions, leaving them to his mother.

Emperor Hui, however, continued to try to protect his siblings. In winter of 194 BC, when Liu Fei, Prince of Qi—his older brother—made an official visit to the capital, they both attended a feast put on by Empress Dowager Lü. Emperor Hui, honoring the prince as an older brother, asked him to sit in a seat at the table even more honored than his own. The empress dowager was greatly offended and instructed her servants to pour a cup of poisoned wine for Liu Fei and then toasted him. As Liu Fei was about to drink the poisoned wine, however, Emperor Hui, realizing what was happening, grabbed the cup as if to drink it himself. Empress Dowager Lü jumped up and slapped at the cup, spilling it. Liu Fei was able to get out of the situation by offering an entire commandery from his principality to Princess Yuan of Lu as her realm. Empress Dowager Lü, who greatly loved her daughter as well, became pleased and let Liu Fei return to his principality.

Emperor Hui died in the autumn of 188 BC of an unspecified illness.

In winter 192 BC, Emperor Hui married Empress Zhang, a marriage that would not yield any children. However, whether Emperor Hui actually had children during or before his reign is a controversial question. The officials, including Chen Ping and Zhou Bo (周勃), who would later overthrow the Lü clan after the deaths of both Emperor Hui and Empress Dowager Lü, claimed that Emperor Hui had no sons—but that Empress Zhang, at Empress Dowager Lü's instigation, stole eight boys from other people, put their mothers to death, and made the children her own. Modern historians have split opinions on the issue, but largely believe that the boys were actually Emperor Hui's sons by concubines and that Empress Zhang did indeed put their mothers to death and make them her own children. (As, for example, Bo Yang pointed out, it would be logically incongruent, if Empress Zhang did steal these children from elsewhere, for her to put only the mothers but not the fathers to death.) Under this theory, the officials denied the imperial ancestry of these children in fear of the fact that they were also descendants of Empress Dowager Lü and her clan, and therefore might avenge the slaughter of the Lü clan—a reason that they themselves admitted. Except for Liu Gong (who was deposed and executed by Empress Dowager Lü), the other children either died young by natural causes or were executed by the officials after they made Liu Heng, the Prince of Dai (Emperor Wen) the emperor.

One can perhaps analogize these princes to the English "Princes in the Tower"—innocent children who were the victim of dynastic infighting and their own bloodlines.

• Father
  • Emperor Gaozu of Han (2nd son of)
• Mother
  • Empress Lü Zhi
• Wife
  • Empress Zhang Yan
• Children
  • Crown Prince Liu Gong (劉恭), later Emperor Qianshao, executed by Empress Dowager Lü in 184 BC
  • Liu Shan (劉山), later renamed Liu Yi (劉義), later re-renamed Liu Hong (劉弘), initially made Marquess of Xiangcheng and later made the Prince of Hengshan (the first name change might have been required by this change in title, as it is considered inappropriate in ancient China to have one's name (or one's male ancestors' names) share characters with one's titles), later Emperor Houshao, executed by the officials in 180 BC in the aftermaths of the Lü Clan Disturbance
  • Liu Chao (劉朝), initially made the Marquess of Zhi and later made the Prince of Hengshan, executed by the officials in 180 BC
  • Liu Wu (劉武), initially made the Marquess of Huguan and later made the Prince of Huaiyang, executed by the officials in 180 BC
  • Liu Jiang (劉疆), the Prince of Huaiyang, died in 183 BC of unspecifed natural causes
  • Liu Buyi (劉不疑), the Prince of Hengshan, died in 186 BC of unspecified natural causes
  • Liu Tai (劉太), initially made the Marquess of Changping and later made the Prince of Jichuan, executed by the officials in 180 BC

Emperor Hui's most trusted companion was documented by Sima Qian, China's Grand Historian: