Well im writing my fantasy novel and i came up with several more countries along with the many others i came up with. I was thinking too many countries would boil down to too much information that would drag on. (maybe i could just write a book explaining the Histories of these Countries). But if i have a good 40-50 countries if not more, would that be too much to keep up with? I want a detailed setting, but as before i want enough detail for the readers to visualize on their own accord. Some countries are mentioned in the trilogy im writing but others i want to add in but have parted with the other countries to fight for themselves.
I could see it going either way. If your world is rather large, it seems fitting. Our own planet is vast and differential with plenty of variations of countries and races. On the other hand, I doubt any reader could keep up with that many lands. Information dumping would seem like an outcome that might be inevitable in trying to explain this many places and their varying people. If you opt to keep and mention these country in an index or glossary in the back of your book so readers can check if unsure. If you can make it happen, it could be believable.
Worlds that are too small feel unrealistic, in my opinion. On the other hand, information dumping is only a good thing very,very rarely. Only nations relevant to the story should be mentioned, and not all in one spot. You can give hints through dialogue about anything if you want, and including a more comprehensive glossary is a good idea. Additional nations or expanded lands could also be good settings if you plan on allowing other people access to your world, or if you plan on sequels. It's your story, though. You're the best judge of your abilities, and ultimately only you can decide what fits and what doesn't.
I don't think having created a vast, detailed world is a problem at all. But as others have pointed out, knowing what to tell the reader about and what not to tell them is the key. Many fantasy writers, particularly starting out, create detailed worlds and then take the view that the reader is damn well going to know everything about the world the author spent so much time creating, whether the reader wants to or needs to. That's likely to cause a reader to put the book away and never pick it up again. Knowing all of that detail as an author can make your world seem authentic, and can provide you with a lot of option for future stories. But don't force the reader to take in all of that information.
It's well and good having all these countries... but is the story actually going to use them all? Essentially that's the point of creating the world in the first place, is it not?
It is your world. If you feel like having 900 countries go ahead. Fantasia/Fantastica had an infinite amount of countries in it but only introduced the relevant ones. I would imagine that is how you would end up doing it as well. I don't need to know about a desert country that isn't going to be used till chapter 32 in chapter one. So use as many as you feel.
I'd use a map and glossary to give the reader an insight. Then, as has been mentioned, bring up the lands as and when relevant in the story.
I find it hard to believe that upwards of forty countries will play significant roles in a single novel, particularly a first novel which will need to be in the 80k to 120k range (preferably 80k to 100k). You can certainly mention more countries than the few principal locations, but it's a waste of time and effort to go into great detail designing countries that will not be used in this novel. Whatever you do, don't infodump. Provide the reader with the details he or she needs, no sooner than needed, and very little more.
