Love him or loathe him – and there are plenty of reasons for both – Genghis Khan was undeniably one of the most impressive figures in world history. Born into a small nomadic tribe near Lake Baikal, Temüjin, as he was originally named, grew into the man who united Mongolia and ruled over an empire that spanned from the eastern edge of China to the Adriatic Sea.
And despite all that, he’s somehow most famous today for boning.
That’s right: chances are you’ve been told at some point that some surprisingly large percentage of the population is directly descended from old Genghis himself. But is it true? Are we really surrounded by homeopathic Hordes? Or is this just another mathematical inevitability, like being related to Charlemagne?
How many people are descended from Genghis Khan?
The history of this factoid goes back nearly 20 years, to a groundbreaking 2003 historical genetics study. When sampling DNA from 16 populations across Asia, researchers were surprised to find that nearly one in 12 men on the continent shared an unusual Y-chromosomal lineage – one that they said likely came from Genghis Khan.
What made them so sure? After all, it’s not like they could go take a cheek swab from the man himself – so, instead, they relied on clues from science and history to fill in the gaps. So, for example, the idea that the unique Y-lineage may just be due to natural population expansion is a no-go: “If this spread were due to a general population expansion, we would expect to find multiple lineages with the same characteristics of high frequency and presence in multiple populations,” the researchers explained, “but we do not.”
Statistical analysis ruled out the Y-chromosome lineage turning up by chance: the probability of that was about one in ten-octoseptuagintillion, a number so large that we literally had to build it up from the Latin roots just now due to a lack of existing terminology – if you want to try writing it down, it’s one followed by 237 zeroes, so use a big piece of paper.
So if it wasn’t chance, what else could it be? Simple biological selection – the result of one impossibly sexy man that roamed the Mongolian steppe all those years ago? Again, it’s possible but highly unlikely, the researchers decided: “the small number of genes on the Y chromosome and their specialized functions provide few opportunities for selection,” they wrote, making it “therefore necessary to look for alternative explanations.”
So they turned to another type of genetic pressure – one that, in humans, is maybe even stronger than biology.
“This is a clear [demonstration] that culture plays a very big role in patterns of genetic variation and diversity in human populations,” geneticist Spencer Wells, one of the 23 co-authors of the paper, told National Geographic at the time. “It's the first documented case when human culture has caused a single genetic lineage to increase to such an enormous extent in just a few hundred years.”
To put it in simple terms, Genghis Khan – and his sons and grandsons after him – was considered “genetically fit” not because he was strong or good at hunting necessarily, but because he was Khan. The populations his armies conquered were often slaughtered en masse, decimating the potential gene pool for future generations – and, importantly, the family line continued to rule large areas of Asia as late as the mid-19th century by some measures.
In other words, the genetic line showed that about 8 percent of men in the region of the former Mongol empire, and therefore about one in 200 worldwide, share one single male ancestor – and based on a combination of logic, statistics, and common sense, that ancestor was almost certainly Genghis Khan.
How many children did Genghis Khan have?
From what we know, the Khan certainly had enough opportunity to become the ancestor of an estimated 16 million descendants. He married his first and principal wife, Börte, at the tender age of nine – which sounds really bad, but records state that they didn’t live together “as man and wife” for a further seven years – and would go on to take six more throughout his life: Yesugen and her sister Yesui, Khulan, Möge Khatun (technically a concubine, but who’s counting), Juerbiesu, and Ibaqa Beki.
As well as these ladies, legend has it that he also kept as many as 500 concubines – often noble ladies and princesses from conquered tribes and lands – and fathered a similar number of children. Popular though this story is, it’s completely unverifiable: because of Mongol custom, Genghis likely only recognized his four sons by Börte as legitimate heirs, with the identities of the rest of his children, including even the five daughters Börte bore him, lost to history.
Nevertheless, David Morgan, the late historian of Mongol history, told The New York Times in 2003 that it was “perfectly plausible” that the Khans would have had so many children. Tushi, for example, the callipygian-named eldest son of Genghis, was recorded as having 40 sons alone, and “it's pretty clear what they were doing when they were not fighting,” he said.
Does anybody else have as many descendants as Genghis Khan?
As prolific as the Khan’s legacy is, it is not unmatched. A 2005 study found another Y-chromosomal lineage, also in eastern Asia, which was present in around one in thirty men sampled – not much compared to Genghis’s brood, but still a huge number.
This lineage, the researchers worked out, started around 500 years ago – right around the time China was undergoing a seismic political change known as the Ming-Qing transition.
“We reasoned that the events leading to the spread of this lineage might have been recorded in the historical record, as well as in the genetic record,” the study explained. “[The Qing] dynasty was founded by Nurhaci (1559–1626) and was dominated by the Qing imperial nobility, a hereditary class consisting of male-line descendants of Nurhaci's paternal grandfather, Giocangga (died 1582), with [more than] 80,000 official members by the end of the dynasty.”
Once again, the researchers found evidence of this social pressure favoring one genetic lineage over others – the lineage of Giocangga. “The nobility were highly privileged; for example, a ninth-rank noble annually received ∼11 kilograms [24 pounds] of silver and 22,000 liters of rice and maintained many concubines,” they wrote. “A social mechanism was thus established that would have led to the increase of the specific Y lineage carried by Giocangga and Nurhaci and to its spread into a limited number of populations. We suggest that this lineage was the Manchu lineage.”
And later, in 2006, researchers found another noticeably widespread Y-chromosome lineage – this time stretching from the Middle East to the western coast of Ireland, where as many as one in five men were found to share the genetic signature.
Which super-fertile ancestor was responsible for this third lineage? The legend that has grown up around the study has him as Niall Noígíallach, or Niall of the Nine Hostages, a semi-to-completely mythical fifth century king who supposedly started the Uí Néill dynasty of Ireland. But while it’s a pretty tempting origin myth if you’ve Irish blood in you, we should point out that the conclusion is not without controversy – and that one of the researchers behind this study told the New York Times that he was “as surprised at finding evidence that Niall existed as he would have been to learn that King Arthur had been real.”
And those are just the lineages that have names attached. In 2015, researchers found 11 particularly strong Y-chromosome lineages in populations across Asia: the Khan lineage, the Giocangga lineage, and nine others originating from unnamed ancestors who lived between 2100 BCE and 700 CE. While world history and ancient politics allowed the team to suggest a few candidates for these fecund founders, ultimately, their identities will likely remain unknown.
None of these mega-patriarchs come close to Genghis Khan’s output though – at least, we don’t think so. Because of course, there’s one problem with saying that 16 million people are direct descendants of Genghis Khan: we don’t actually have any DNA from the Khan himself.
“Looking for these links is fascinating. When we did it, we were using pretty indirect lines of reasoning, and you could try and do that with each of these lineages,” Chris Tyler-Smith, an evolutionary geneticist and lead author of the original 2003 paper, told Nature. “What I really hope is that at some point someone will find Genghis Khan's tomb and remains.”
All “explainer” articles are confirmed by fact checkers to be correct at time of publishing. Text, images, and links may be edited, removed, or added to at a later date to keep information current.