patrick.net

I'm dual Irish/American. Back in the day (1980's), it was pretty easy to do.

Essentially, if you have to qualify for citizenship, as opposed to automatically qualifying, then you might risk your US citizenship. This sounds somewhat confusing, but the laws have changed over the last 50 or so years. The oligarchs want safe havens, so they liberalized the joint citizenship laws to facilitate their bugout plans.

The easiest way is to contact the nearest embassy from which you can claim ancestry. Ask them to forward you the documentation for either (1) applying to be listed on the foreign births registry, or (2) if you don't have to do that, just apply for a passport. You need to provide birth certificates to prove that you are descended from a former citizen of that country. It greatly helps in case 2 that your parent or grandparent can provide the documentation.

Be advised, since the global meltdown, many foreign embassies have substantially reduced their footprint in the US, so you might have to actually go to the "home country" to conduct this business. Again, contacting the embassy is your best bet. If you have the money, then let a lawyer do it; otherwise, you can do it yourself for under $500 (registration and passport fees).

Dual EU and US here. Totally worth it. But I first had EU then became US citizen, so prob different process for you.

Only reason I would ever do this is if I wanted to retire in Europe.

Not hard to get a Mexican passport. My wife has the paperwork, so myself and the kids all qualify automatically. Always a good idea to have more than one just in case..