Emperor Duc Duc’s real name is Nguyen Phuc Ung Ai. He is the second son of a royal couple Sir Nguyen Phuc Hong Y and Madam Tran Thi Nga. He was born on January 4th of the lunar year of Quy Suu (on February 11st 1853 solar calendar). In 1869, Emperor Tu Duc received him as his adoptive son and renamed him Ung Chan. After that, Ung Chan lived in Duc Duc Palace (his private palace offerred by Emperor Tu Duc) and was brought up by Madam Vu Thi Duyen (later entitled Queen Le Thien Anh).

Before passing away, Emperor Tu Duc prepared a Decree to descend the throne to Ung Chan that stated his worry as follows: “… because Duc Duc has a physical defect in his eyes and a lustful habit, so I’m afraid that he will not be judicious enough to handle great affairs of the country. It will be a good luck for a country under the reign of an old emperor, thus how it would be if I don't chose him for that position ?”.

At his installation for the crown, Ung Chan ordered to skim this statement, so he was three days later dethroned and imprisoned until the death by two regent highranking madarins named Ton That Thuyet and Nguyen Van Tuong, under the order of Queen Mother Dowager Tu Du (Emperor Tu Duc’s Mother) and Queen Le Thien Anh (Emperor Tu Duc’s wife).

He passed away on September 6 of the year of Giap Than (October 24th 1884 solar calendar) at the age of 32.

In 1892, he was honoured the title Emperor Cung Ton Hue by his son Emperor Thanh Thai.

Emperor Duc Duc had 19 children (11 sons and 8 girls).