obtaining dual citizenship when born on a military base

Welcome to the forum

As far as I know any military bases overseas are classed as being part of whatever country is occupying that area, the same as Embassies.  So, in your case, the base is part of the USA.
Your birth country would be USA and you are an American citizen born of parents who are both American so I would think you have no chance of gaining Spanish citizenship.
You could contact a Spanish Embassy for information / advice.

I suggest an in depth online search for information.

ok thanks.

Hi and welcome to the Forum.

I can confirm what Stumpy has said, but to add a bit of meat and terminology.

Your parents would have been based in USAREUR as part of the USA contribution to NATO and as such, subject to the Status of Forces Agreement in place at the time between the USA and whatever host country they were serving in; what these agreements agreed, amongst other things, were matters like residency/citizenship for US citizens serving and any children born there while the parents were subject to the Agreement; you can download a copy of the Agreement from the US State Department website; this link will download a PDF copy straight to your PC.  My experience was that foreign nationality was only passed on to a child if one of the parents had citizenship of the host country.

2 of our 3 kids were born in a military hospital in Germany, none of them was entitled to German nationality.

I don't think you or any of your offspring will qualify for Spanish citizenship, but you could try speaking direct to the US State Department to see if there were any special circumstances extant at the time of your birth that may mean otherwise.

Hope this helps.

Cynic
Expat Team

ok. Thank you for the follow up information. It is much appreciated.