Thanks for the article. You captured a few points well, but I think you went into the rabbit hole with others.
Like any unbelievable story, it was a superposition (just to use some physics jargon) of many factors. I collected a few below, definitely not exhaustive, but I hope I captured the main ones.
1. Budapest was actually a metropolis and melting pot in the second half of the XIX. century
2. These scientists had world-class education (in Hungary and in Germany/Switzerland)
3. Emigration to the US that has become a superpower in the XX. century
1. Historical background / Budapest, the melting pot
Let's put this into context. Hungary was occupied by the Osman empire from the mid 16th till the end of 17th century. The Habsburgs helped to kick out the Turks so Hungary became a part of the Habsburg empire (no Austria-Hungary yet). Both politically and economically undeveloped: feudal system, agriculture heavy, little industry. The Habsburg empire was archaic compared to Britain or even France and Hungary was less developed than the (current day) Austrian or Czech territories. In the 19th century the feudal system started to break up, the Hungarian noble class wanted more autonomy, but the Hungarian revolution of 1948/49 was beaten. However, the Austrian empire was defeated by Prussia in 1866 and Austria realised that it needed to change tack (it gave up its aspiration to lead the German unification). In 1867 the so called Austro-Hungarian Compromise was signed. Lot of details, 2 important points here: 1. Customs union 2. Common Army. The economy boomed in the next c.50 years, and with lower spend on military the government had plenty of extra resources and it spent the money wisely.
A, Education reform of 1868:
Hungary introduced a Prussian-style "volkschule" system in 1868 (compulsory for both boys and girls between age 6-12 and free, at least for the poor. FYI: At this time, neither France nor Britain had such a broad coverage.)
B, Budapest, the economic hub
Vienna was the political centre of Austria-Hungary, Budapest “got” the role of the business capital. First, Budapest was kind of detested by Vienna, like okay, you can have the less glamorous business role, but Budapest ran with the opportunity. It became an economic and trading hub attracting people not just from Austria-Hungary, but from all over Europe.https://www.reddit.com/r/MapPorn/comments/asdj7h/europes_largest_cities_by_population_in_1900/
C, Second industrial revolution - electricity
As I wrote above, Hungary was much less developed then even the Austrian or Czech territories (even around 1900, GDP/capita was c.50% higher in “Austria”, 2x in Germany and 3x in Britain https://brilliantmaps.com/europe-in-gdp-per-capita-1890/ ), but Budapest managed to ride the electricity boom, its companies and inventors played an important role. These were the high-tech companies of the time, imagine like the headquarters of Taiwan Semiconductor or Salesforce would be in Budapest. Just a few examples:
Nikola Tesla worked for Puskas before he moved to the US. There were some other remarkable scientists and engineers working for Ganz and Tungsram. (see the Key people section on Wikipedia)
The 3rd oldest underground in the world (first 2 in Britain) is in Budapest and its construction was an engineering miracle that time, it took less than 2 years.
Sidenote: In 1867 legal equality was granted to the Jews (emancipation). This opened the door to their rise in social ranks. The timing was perfect. C. 5% of the Hungarian population was Jewish, but they were overrepresented in cities as they did not own land (the primary source of income and wealth in the feudalistic times). education was their way to rise and they used their talents to help to build out the budding capitalist system and the industrial sector. Given the economic boom, c.25% of Budapest population was Jewish by 1900.
Hungary had a great, if not world-class, primary and secondary education system then (see above) and some of these scientists had private tutors from a very young age. The Hungarian universities were not world-class though, the best were in Germany. (At this time, the scientific epicentre was Germany, even the “language of physics” was German). These scientists came from upper middle class or wealthy families, so they could afford to go to university in Germany (or Switzerland). They did not just learn the most recent achievements of science from the greatest minds of the era (Neumann’s doctoral advisor was the great David Hilbert, Teller’s was Heisenberg!), but also studied and worked together with probably the most talented students of the time.
I think having a Jewish background played a role here. Even though they were wealthy, they were not part of the noble class, so they could not expect a cushy, well-paid office job in the government, etc, so they brought the maximum out of their talents. E.g. Both Teller and Wigner enrolled into the Budapest University of Technology (the most prestigious institution in Hungary) but they soon realised that it was not good enough for them and went to study in Germany.
Also relevant, that all of these guys were interested in theoretical fields (physics and maths), but their fathers pushed them to study chemical engineering so that they can make a good living. They obliged, but this did not discourage them to study their primary interests, earning a second degree in math/physics. Imagine how broad their knowledge was!
I do not believe in the Jews have / had higher IQs argument, I believe it was more of a nurture thing. The Jewish population was mostly urban and education was their best way to rise. They needed to figure out ways to make money, they did not have land to plough on.
3. Emigration to the US
Austria-Hungary lost in World War I, the empire dissolved, Hungary lost a large part of its territory. The number one objective of the country was to challenge the Peace Treaty. The country became extremely nationalistic, Hungary aligned behind Germany. Anti-Semitism intensified in the 1920s and particularly in the 1930s.
For these Jewish scientists (even if some of them were secular) the best option was to emigrate to the US. Europe was too dangerous and the US invested in science and it was a much more open society. (Although these guys remained outsiders nonetheless).
In the US they worked with the brightest of the era again in a country that had close to unlimited resources. And seeing the events in Europe made them paranoid (who wouldn’t have been?!), propelling them to work even harder. (The Einstein-Szilard letter was Szilard’s idea, because he was concerned that if the Germans invade Belgium they could access uranium in larger amounts from Belgian Congo)