It depends how you see things.
Romania has been vassals of the Ottoman for two centuries, before being annexed by Ottoman, Austria, Russia.
It became independant later again.
Does it mean there was nothing before ?
Should we consider like the CIA fact book does that Russia exists only since 1991 with the breaking of USSR? If I remember correctly, their was a Russia during WWI, a Russia in 1812 (we know it all to well), etc.
But before their declaration of independance, The USA never existed as an independant country.
From that point of view, Romania is older.
Well, what can I say - in the military, they call it a "break in service", i.e. it's not continuous. And for such a thing, there's a penalty. Basically, you don't reap the benefits of one that has non-stop, continual service... especially if the break was long in duration.
But regardless, I don't make the rules, I'm just reading text... text which states certain dates (not attempting to rhyme). But here's the thing, let's take Finland for example. First of all, I'll just forget that horrible experience I was dragged through last page by bitter Vikings in long-term decline, and just use this example: First of all, what is a country? If all the land (of Finland in this case) is officially part of "Russia", then, where is Finland? Is it a country? Technically no. Then, suppose Finland comes back in 1917... there it is again. "Born again", as they say in Christian circles.
So, there's different ways to think about it:
A) Longest, continious running - the U.S. since 1776 for example.
B) Cumulative time - 'Romania' was around for many centuries, with a few complications, but it has more overall 'time in existence'.
Which should count, and why? Well, today, if we somehow could manage it, we could recreate the "Holy Roman Empire", using the same exact borders. Sure, a lot of the same people - their decendants, same towns/cities, routes (now paved), etc. Now how old is this country? Is it really the Holy Roman Empire? Just because "we say it is", and "we want it to be". But, in reality, it is a new country.
Countries rise and fall (with varying degrees of 'fall'), just because they re-emerge with the same name, decendants, and land area, "just because they want it", or were granted it by some treaty... hey, it's a new country. OK, fine - the culture is still there... that's not easy to get rid of. But the country is new.
So, technically, "new country". Old land, though. Same, or similar name. But, a new formation/creation.
I'm sure this post will be picked apart without mercy. I was just trying to express my point of view in reponse to Steph's question. That's it.
Summary:
Culture: Cumulative time (Most of Europe is older)
Country: Continuous time (Different story)