User blog comment:Freelance Grammar Nazi/Kind of a Rant...?/@comment-1151277-20100710190650

I tend to agree with the notion of "flesh out the characters that are already there"

Also it must be taken into account that each country has a ton of history that comes along with it - and there's also a lot of cultural information that needs to be taken into account too. Creating new characters for countries that Himaruya doesn't know a lot about and making sure that their personalities and interaction with other countries reflects historical/cultural/stereotypical (to a degree) context is probably very time consuming.

Granted there are some countries that probably wouldn't fall under this explanation (Ireland, Mexico, and India spring to mind) However, creating characters for this countries may be difficult, as some of their primary interactions during the time period Hetalia focuses on may be with countries that don't have characters either, and requiring even more characters to be created and thus a domino effect appears.