Nonetheless all counties there were dirt poor at some point in the last hundred years. North Korea still is. IQ is largely a measure of education, which itself

Nonetheless all counties there were dirt poor at some point in the last hundred years. North Korea still is. IQ is largely a measure of education, which itself is largely related to how developed your country is. Large groups of relatively uneducated rural dwellers will drag the average down. It's well known Asians are smarter, whether for cultural or genetic reasons, but the devil is in the details. If you look at average populations I would expect the inverse for counties like China that only developed recently.