I'm a U.S. citizen looking at studying in Europe. Right now France or Germany seem like the best/cheapest places (but open to suggestions!). I've had a few people tell me that if you graduate from a French university, if you live there for a further 3 years, you are eligible for French citizenship? It can't be that easy. I've tried looking everywhere for this, but can't get a straight answer.
It's relatively easy, yes, but there are several caveats:
- You need to become a resident in France before you apply (and this requirement is assessed more broadly than residence for, say, tax purposes). It's reasonably easy if you have family/marry someone (a registered partnership or PACS is good too), not so much if you want to qualify for a work permit after graduating. A paradox of the constant tightening of the rules about entry and stay is that it's now almost as easy to get citizenship as to stay long-term. Having a spouse or children living abroad is also taken as evidence that France is not the “center of your interests” and therefore that you are not a resident for this purpose.
- It's a requirement for naturalisation, which means that the merits of your application will be evaluated by the relevant authorities. As far as I know, the odds are not bad but it's not automatic. To qualify for déclaration (which means that you are more-or-less entitled to become French if you want to, with very little discretion left to the civil servants who will process your application), you again need to marry someone or be born in France.
- One key requirement in any case is speaking French. Association with certain forms of Islam perceived as radical (especially the Salafist movement) have also been used to refuse applications. All this stems from a more general “assimilation to the French community” requirement.
How difficult it is does not only depend on the law but on the instructions given to civil servants. To give you an idea, until 2009 or so, 100000 people became French by naturalisation every year (many more became French through other procedures like déclaration) and 25% of the applicants were turned down. Recently, it's down to 40-50000 people, with only 50-60% success rate but the current government announced it wanted to come back to the older regime. So the residence requirement isn't everything there is to it.
In practice, if you speak French and have a stable job, you stand a very good chance of getting citizenship. Everything is much more difficult if you don't have a job or stayed illegally in France in the past. Same thing if you still have a student residence permit (you are not considered a resident yet in this case) even if official instructions issued last year explicitly ask to consider applications from “young graduates” and “students with high potential” favorably.
Note that having studied in France reduces the number of years you have to wait before applying but everybody can apply for naturalization after five years of residence. Technically, the requirement is two years of residence if you spent two years studying “successfully” (article 21-18 of the code civil) so four years in total, almost the same than the general requirement. Also, if you studied five years in a country where French is an official language, there is no duration of residence requirement. But I have also read about people who fulfilled the conditions and still received an ajournement (which means the application was not rejected outright but delayed for one or two years). The most important thing is really having a stable situation.
Anecdotally, I know many people who have become French citizens, but most of them did it through the family route. The choking point for friends from abroad who studied in France is usually renewing their study visa and transitioning to another status at the end of their studies. If you can manage that, citizenship is not very difficult to get.
Also, France does not require you to give up your previous citizenship so if your current nationality allows it and there is no treaty preventing it (and that's the case for the US, as far as I know), you can easily become a dual citizen (it's generally not the case in Germany, I think). You do have to report what other nationalities you have and intend to keep.