More incredible is how the Kalenjin tribe, with just 5 million individuals, dominates most of the Kenyan wins. To quote Wikipedia "from 1980 on, about 40% of the top honours available to men in international athletics at these distances have been earned by Kalenjin".
In the world of sport, no other country seems quite as dominant, except for maybe the Canadians participation in NHL hockey (at about 50%), but this sport is not universally played. And to a lesser extent there are Jamaicans in sprinting, eastern Europeans in weightlifting, Romanian gymnasts, and Russian females high jumpers.
Nevertheless I had to pause and wonder about whether this sheer uniqueness of Kenyan running was in itself unique. Therefore I began to consider which other countries, at given epochs, had also dominated a single activity. Hence I want to focus on math, a discipline, like running, that in theory should be practicable anywhere.
Early 20th century Hungarian mathematicians: Hungarian mathematicians were not merely good, they were world-changing. The outcome of WWII and world history beyond was directly influenced by their migration to the United States. Consider the wiki list here, which includes Paul Erdős (who practically co-authored every math paper in his field), Pólya, Bolyai, Stanislaw Ulam (co-designer of the H-bomb), Szilard (conceived the notion of nuclear reactors and the A-bomb), Arpad Elo (inventor of the eponymous chess rating system), Edward Teller (theoretical physicist, co-designer of the H-bomb and various quantum solid-state principles), and von Neumann (involved in just about everything, including the world's first re-programmable computer, game theory and DNA). You may have noticed nuclear weapons were mentioned several times among these names. The US government wanted nothing more than to win the nuclear arms race and with no deliberate aim to favour any particular group, Hungarians were often at the forefront throughout its history.
To quote a paper titled the Hungarian Phenomenon offers one explanation:
The 1900s saw the emergence of many bright scientists and mathematicians in Budapest...Stanislaw Ulam once asked John von Neumann about this Phenomenon. Ulam recorded, “When asked about his [von Neumann’s] own opinion on what contributed to this statistically unlikely phenomenon, he would say that it was a coincidence of some cultural factors which he could not make precise”.  Although it is difficult to pin down all the causes of this phenomenon, it is general believed that the Eötvös Mathematics Competition ... and the Journal (KöMal) have played major roles in the development of gifted children in Hungary. In addition, good teachers and the atmosphere of high value on intellectual achievement are also related with the emergence of this phenomenon.Or more dramatically to quote Teller himself (via Turing's Cathedral)
We are Martians who have come to Earth to change everything - and we are afraid we will not be so well received. So we try to keep it a secret, try to appear as Americans ... but that we could not do, because of our accent. So we settled in a country nobody ever has heard about and now we are claiming to be Hungarians.Imagine those living in 1900s Budapest as the Kalenjins of math. Overall, the Hungarians have claimed many math prizes, and not just a few Nobel prizes too (18 in fact, rather incredible since there is no Nobel prize for math). Consider that Hungary is a country of only (at the time) 10 million. Other write-ups attempting to explain include On reputation of the Hungarian mathematics teaching, and A Visit to Hungarian Mathematics, which asked the questions
What is so special about Hungarian mathematics? What made possible the production of so many famous mathematicians in such a small, poor country, in the period between the two Wars?"To which they found two categorical types of answers:
- Practices in Hungary relative to the world of mathematics. I.e. "There was a mathematical journal for high schools, and the contests... once they started, they were self-perpetuating to some extent.
- The trends in Hungarian history and social life. i.e. "Hungary was a poor country-the natural sciences were harder to pursue because of cost, so the clever people went into mathematics".
For anyone puzzled about Kenyan running success, these questions and answers may sound familiar. I have not delved into other dominant competitive enterprises such as chess & Russians, or Music & 19th century western Europe, or peak NYC crime rates in the 1980s. None are cut and dry, so to avoid drawn-out post, I chose Hungarians. It's one not everyone is probably already familiar with, but certainly can be the start of a much longer debate. Cheers.