Seems to me that you have a pretty loose definition of the term Nation OP.
The Dutch Republic
Portugal (15-16th centuries)
Spain (15th-16th centuries)
France (Sporadic, primarily 1789-1813)
Ethiopia (2nd to 6th century AD)
Bit of a silly thread to be honest.
Italy is still somewhat relevant, at least inside EU politics
The Kingdom of Macedon was part of Greece, not modern day Macedonia, leading to
Greece, its still relevant. Just not for good reasons
Turkey is also still relevant thanks to its position in NATO and its quite important to the middle east's balance of power (although its no Israel, Iran, Saudi etc)
Before '41, I'd say the Germans were attempting. Took literately then entire world to take them down. Could also be the UK as >>80340 said. Then the USSR could be counted in afterwards due to them needing to be on par with the US. After they fell, well, America's here and sanding baby.
I kinda feel like the OP means nations that still exist but aren't strong.
Carthage isn't some rump state dottering around in modern-day Tunisia. Carthage was ground into fucking dust. It's dead, kaput. It is an Ex-New City.
(Penny for the reference)
Spain. Spain shit the bed so badly they went from being the ultimate first-rate world power to a fifth-rate European power whose main contribution to the world in the last few centuries has been the invention of the country-wide mid-afternoon nap.
Most of that was Lithuania. Neither Poland or Lithuania are good enough to be great.
When together they're still not good enough to be great. They're good enough to be pretty good though.
Egypt is still relevant
Turkey is a regional power
GB is a top5 power, maybe top10 if you wanna be a douche
Germany cannot into war by design but they are definitely a world power in an economic sense
France is a world power for sure
Iran is a regional power
Saudi was never a power, unless you mean the arab hordes of the ancient caliphates
Tunis and Carthage are unrelated
Ethiopia is a meme
all you had to do was lift the taxes bro, I warned you dog