- Kim Jong Un's mother, Ko Yong-hui, is largely absent from North Korean propaganda
- Ko Yong-hui was born in Osaka, Japan, to ethnic Korean parents from Jeju Island
- Ko was a dancer and Kim Jong Il's partner, but their children were born out of wedlock
North Korean leader Kim Jong Un has built his rule around the Kim family's "sacred" bloodline, but one member of that lineage remains almost entirely absent from official propaganda - his mother, Ko Yong-hui.
Unlike Kim Il Sung's wife, Kim Jong Suk, and Kim Jong Il's mother, Kang Pan Sok, who are celebrated as revolutionary figures in North Korea, Ko Yong-hui has never been publicly honoured in the same way.
North Korea claims that the Kim family belongs to the sacred "Mount Paektu bloodline" - a lineage portrayed as pure, heroic and destined to rule the country. State propaganda says the family's legitimacy comes from this bloodline, according to BBC.
Mount Paektu is located on the border between North Korea and China. In Korean mythology, it is believed to be the birthplace of Dangun, the legendary founder of the first Korean kingdom, although many historians believe he was actually born in Russia.
According to reports, Kim Jong Un's mother, Ko Yong Hui, was born in 1952 in Osaka, Japan. During Japan's colonial rule over the Korean Peninsula, her parents, who were ethnic Koreans from Jeju Island, now part of South Korea, relocated to Japan.
Ko's family relocated to North Korea as part of a government-sponsored resettlement programme when she was about 10 years old. Many ethnic Koreans who immigrated to North Korea from Japan were initially welcomed but were later looked down upon. This clashed with the regime's claim that the Kim family belongs to the sacred "Mount Paektu bloodline."
Ko was a dancer with the elite Mansudae Art Troupe, a prestigious state-run performing group. Japanese journalist Yoji Gomi, who wrote a book about her in 2025, said Kim Jong Il was attracted to her because of her beauty and dancing skills. At the time, Kim Jong Il was already married to Kim Young Sook, the daughter of a senior military official, in a marriage arranged by his father. He was also known to have other partners.
Even so, Kim Jong Il fell in love with Ko Yong Hui, and the couple reportedly had three children, including Kim Jong Un. Because Ko was not Kim Jong Il's official wife, their children were born out of wedlock. Ko and her children reportedly lived in the coastal city of Wonsan, about 210 kilometres from Pyongyang, while Kim Jong Il's official wife remained in the capital.
Experts believe the regime was concerned that her Japanese birth and social background could weaken the Kim family's "sacred" bloodline image. Ko Yong Hui died of breast cancer at a hospital in Paris in 2004. North Korean state media did not publicly announce or acknowledge her death.
How Kim Jong Un became the leader of North Korea is one of the most important questions about the country's leadership.
Kim Jong Il's official wife, Kim Young Sook, had two daughters. Since North Korea has never had a female supreme leader, neither was considered a likely successor. Kim Jong Il also had children with another partner, Sung Hae-rim. Her son, Kim Jong Nam, was once seen as the strongest candidate to inherit power because he was Kim Jong Il's eldest son.
However, Kim Jong Nam reportedly lost his father's trust after criticising North Korea's system of passing power within the same family and calling for reforms. After living in exile in Macau, Kim Jong Nam was assassinated in Malaysia in 2017. Investigators said he was killed with the highly toxic VX nerve agent at Kuala Lumpur International Airport.
Kim Jong Un's elder full brother, Kim Jong Chul, was also considered a possible successor. However, former North Korean diplomat Ryu Hyun-woo claimed he was ruled out because of a serious opium addiction.
With the other potential heirs out of the picture, Ko Yong Hui is believed to have worked to ensure that her second son, Kim Jong Un, would become the next leader.
