It may be more common in the Iberian Peninsula, but I'm wondering WHY people with NO genetic connection to those two nations have hazel eyes too, if it's so rare in others who are able to trace their ancestry quite far back.
“but I’m wondering WHY people with NO genetic connection to those two nations have hazel eyes too”
The Portuguese sailors surely had a lot to do with that.
It’s thought that the green-eyed, blonde people in an area of China may owe their coloring to the survivors of a Roman battle going back to the first century BC - the ‘Lost Legion of Crassus’.
If a genetic influence can be that old, I doubt many people can know who all their ancestors may have been or where they traveled back then.
https://www.warhistoryonline.com/ancient-history/romans-china-lost-legions-carrhae.html