"Den Europeiska Unionen är viktig för Europas länder."
The correct translation of this sentence is "The European Union is important for the countries of Europe." Why is it "the countries" instead of just "countries"?
(The discussion below this sentence is locked, so that's why I'm posting it here)
Europas is in the possessive, so you know exactly to which countries you're referring. It works out the same as a definite.
Because we are talking about specific countries. In Swedish, the s-genitive is followed by an indefinite noun. The English of-genitive is usually used with definite nouns. The sentence sounds incomplete without it, because we are talking about all European countries, not just some. You would need some other word to replace the should you want to emphasise the indefiniteness of countries: for instance, SOME countries of Europe. :)