Emperor Ruzi of Han

Ruzi Ying (Chinese: 孺子嬰; pinyin: Rúzi Yīng; literally: "Infant Ying"; 5 CE – 25 CE), also known as Emperor Ruzi of Han and the personal name of Liu Ying (劉嬰), was the last emperor of the Chinese Western Han Dynasty from 6 CE to 9 CE. After Emperor Ai of Han and Emperor Ping died without heirs, Wang Mang chose the youngest of the available successors in order to maintain his power in the government. The child Ying was soon deposed by Wang Mang who declared the Xin Dynasty in place of the Han. During Xin Dynasty, Ying was under effective house arrest—so much so that as an adult, he did not even know the names of common animals. Before and after the Xin Dynasty was overthrown in 23 CE, many ambitious people claimed to be restoring the Han dynasty. In 25 CE, a rebellion against the temporary Emperor Gengshi used the former Emperor Ruzi as a focus, and when the rebellion was defeated, he was killed. He is often viewed as an innocent child who was the victim of tragic circumstances. (The expression "Emperor Ruzi" is a misnomer, as he never assumed the throne and was only named crown prince. Nevertheless, he is commonly referred to as such.)

In 5 CE, Wang Mang, then already nearly unlimited in power as the imperial regent and fearful that the 13-year-old Emperor Ping, once grown, would retaliate against him for having slaughtered his uncles in 3 CE, murdered Emperor Ping by poison. Because the young emperor had not had any children by his wife Empress Wang (Wang Mang's daughter) or any of his concubines, there was no heir. Emperor Ping's grandfather, Emperor Yuan, had no surviving male issue—of his three sons, Emperor Cheng had no issue, and sons of the other two, Liu Kang, Prince of Dingtao (劉康) and Liu Xing, Prince of Zhongshan (劉興), had succeeded to the imperial throne (as Emperor Ai and Emperor Ping, respectively) and died without issue. The descendants of Emperor Ping's great-grandfather Emperor Xuan were therefore examined as possible successors.

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