The North Korean dictator might be one of the most famous men on the planet, but few details of his private life existed — until recently.
North Korea never strays far from the headlines — and usually, it's for all the wrong reasons.
Last week, the rogue state was in the news again after renewing threats to resume nuclear and long-range missile tests following a breakdown of nuclear negotiations with the US.
The talks had been the first of their kind between the countries in more than seven months — and the breakdown is a worrying sign of potentially escalating nuclear tensions.
Just days ago, satellite imagery revealed numerous worrying "packages" at a top-secret North Korean nuclear site with deadly potential.
That's because Mount Paektu is the country's highest mountain, the rumoured birthplace of the founder of the first Korean kingdom thousands of years ago — and a place the leader regularly visits ahead of major announcements.
According to the BBC, "there's speculation that this time Kim could be rethinking his promise to refrain from testing long-range missiles and nuclear weapons".
It has also been interpreted as a way of attracting the US's attention, after giving the Trump administration a late 2019 deadline to devise a denuclearisation deal.
But while Kim Jong-un is one of the world's most feared men, he's also one of the most mysterious, with very little known about his private life and childhood — apart from a string of bizarre myths, such as his weather-controlling powers.
However, in her recent book, The Great Successor, biographer Anna Fifield managed to dig up some fascinating details of the leader's personal life.
In an interview with Vox earlier this year, she described him as a pampered child raised to believe his own greatness.
"He was a spoiled brat. He was brought up to believe that he was a demigod from the age of three or four, probably as long as he can remember. He was given a specially modified car so he could drive it himself at the age of seven," she told the publication.
"Then there was the time the family's personal sushi chef, who had basically been hired to be Kim's friend, went fishing for sea bass with Kim and his brother."
Fifield said while many believed Kim Jong-un's time at a Swiss school in the '90s would make him a more moderate leader than his predecessors, the reverse was actually true.
"What his time in Switzerland must have taught him is that if it wasn't for the family myth and family dynasty, he'd be a nobody. He would be another ordinary, chubby immigrant kid going to school and struggling with his math homework," she told Vox.
"He would not, in other words, be the demigod he had been raised to be."
UNDERCOVER PRINCELING
In her book, Fifield also goes into deeper detail about Kim Jong-un's time in Switzerland.
The future leader first left Pyongyang in 1996, joining his older brother Kim Jong Chol, who had already been living in the Swiss capital Bern for two years.
The boys attended the same exclusive private international school, and lived with their maternal aunt and uncle, who masqueraded as the boys' parents.
"We lived in a normal home and acted like a normal family. I acted like their mother," Kim's aunt told the author.
"Their friends would come over, and I would make them snacks. It was a very normal childhood with birthday parties and gifts and Swiss kids coming over to play."
Fifield also managed to track down some former schoolmates of the North Korean leader — and collect some fascinating anecdotes.
"He kicked us in the shins and even spat at us," one classmate was quoted as saying in the book, although another described him as "ambitious but not aggressive".
Despite Kim Jong-un's unique upbringing, Fifield also describes regular teenage hobbies, including obsessions with basketball, Adidas tracksuits and Jean Claude Van Dame movies.
However, he was widely considered to be "a weird outsider" because of his introverted personality, refusal to wear jeans like his classmates, and his avoidance of parties, alcohol, girls and school camps and discos.
Two years after Kim Jong-un arrived in Switzerland, his mother was diagnosed with breast cancer.
His aunt and uncle feared her death could endanger their lives and those of their children's — as Fifield explained, "their link to the regime, the relationship that had vaulted them into this privileged position, was becoming weaker by the day."
In 1998 they bundled up their family and fled to the US embassy, abandoning their nephews.
They explained their situation, applied asylum in the US, and were soon granted asylum.
As a result of the upheaval, Kim Jong-un was transferred to a different, German-speaking public school, where he remained until 2001.
At some point during that year, the teen disappeared, telling one friend his father had ordered him to return to North Korea.
His fellow students never saw him again — until he reappeared "on the balcony of a majestic building in the middle of Pyongyang with his father, having been crowned The Great Successor" a decade later, Fifield wrote.