How many "famous" people do you know, weelittledrummer, who come from a town of a half million people?

I suppose it depends what you mean by "famous".

Two cities generally reckoned as highpoints in human culture (which doesn't mean they weren't deeply flawed in other ways) were 5th century Athens and 14th century Florence.

5th Century Athens had about 200,000 people in all.

14th century Florence had maybe 80,000.