El Salvador is the first country to make Bitcoin a legal tender but as of this moment, it isn't been passed to the congress so there is a slim chance that it might not happen but I'm optimistic on it and for sure it will pass into the congress.

If this will be a success then it will be good for the crypto users and this might create a domino effect towards other small countries and they might do the same... or not . On the other hand though, I don't expect for some 1st or even 2nd world countries to do the same as what El Salvador did.