You have to go to a little lost corner of the tourist island of Jeju to find the graves of the Ko family, ancestors of Ko Yong Hui, mother of the current dictator of Pyongyang.

Jong Un is the third of the Kim dynasty to rule North Korea, after his father Jong Il and his grandfather Il Sung, what official hagiography calls “the Paektu lineage”, named after a sacred mountain in the north of the peninsula.

Behind this heritage from father to son hides the unmentionable fate of Jong Un’s mother, born in Osaka in 1952, of parents from Jeju and having emigrated to Japan in 1929 when the Korean peninsula was a colony of Tokyo.

Several members of his family, including Kim Jong Un’s great-grandmother, are buried in Jeju, in a simplicity that contrasts with the Kumsusan Sun Palace in Pyongyang where the bodies of his father Kim Jong Il and his grandfather Kim Il Sung.

When Kim came to power in 2011, several experts pointed to his mother’s past, but Pyongyang has never confirmed.

– Repatriation program –

The regime “must have feared that a confirmation would undermine its legitimacy,” Cheong Seong-chang, from the center for North Korean studies at the Sejong Institute, told AFP.

The Kim dynasty based its power on Kim Il Sung’s role in the guerrilla warfare that drove the Japanese from the peninsula in 1945.

“A Korean-Japanese heritage goes directly against the North Korean myth of his leadership,” Cheong said, explaining Kim’s difficulty in publicly admitting his family’s ties to Osaka.

Kim Jong Un’s mother grew up in Osaka before her family took part in a repatriation plan put in place by Pyongyang in the 1960s.

The program urged Koreans living in Japan to move to North Korea, as part of a campaign to “claim supremacy” over the South, says Tokyo-based novelist and columnist Park Chul-hyun.

“The North saw the Korean-Japanese community as a strategic battleground,” he adds, and succeeded in convincing nearly 100,000 ethnic Koreans to resettle in the “socialist paradise.”

Among them, the Ko family lived a relatively normal life in the North until one day their eldest daughter came to the attention of the ruler’s son and likely successor.

– “Empty grave” –

Miss Ko, a dancer, married Kim Jong Il in 1975, according to experts, and bore him three children. She died in 2004.

“The official media did not speak about Ko Yong Hui”, underlines Rachel Minyoung Lee, researcher of the 38 North program at the Stimson Center in Washington.

Apart from demonstrating that he is the legitimate heir to the lineage of Mount Paektu, the official media do not mention the roots of Kim Jong Un, she adds.

The South Korean press discovered the Ko family graves in Jeju in 2014, holding one of the earliest confirmations of Kim Jong Un’s South Korean ancestry.

At the time, a plaque – known as the “empty grave” in the South – honored Kim’s maternal grandfather, Ko Gyong Taek, who died and was buried in North Korea.

“Born in 1913 and left for Japan in 1929. He died in 1999,” read the plaque, which, according to custom, allows relatives to practice their rites to the dead, even if the body is not present.

The plaque was no longer there when AFP visited last April.

According to the Chosun Ilbo daily, it was removed by a distant relative of Kim Jong Un, shocked by the media attention and fearing an act of vandalism.

He assured the newspaper that his family “didn’t know anything about his relationship with Kim Jong Un” before the press found out.