USA, and USSR Soviet UnionUSA & Russia maybe?
The Union Of Soviet Socialist Republics and The United States of America. EasyUSA, Soviet UnionUSA and USSRParaguay and Burkina Faso.The US and USSR. I think the Klingons were more like the Japanese, with talk of honour, death in battle and fighting to the last man. All similar to Japanese culture. The Romulans are a closer representation of the USA opinion of Russia, i.e. trecherous and deceitful with a tense neutral zone where neither side can enter without starting a war where there would be no clear winner.Probably Russia and the United StatesThe US and the Soviet Union.
I see the most similarity with the Federation representing WWII-era USA, and the Klingon Empire representing Japan.
The conflict with the Romulans was more like the Cold War: Humans mirroring the US, and with Vulcans and Romulans sharing a common heritage, Vulcans representing democratic Europe, and Romulans representing communist Europe.
But of course, all this is speculation.
I see the cardassians bEing the nazis with there smug we are the superior race thing. The jemhadar being the Russians with there communist views of the founders being the be all and end all of leaders. The bahorins being small and religious being like Tibet/India. And the Klingons being like the Japanese with every thing being about honor and having a empire with a emperor.
It isn't possible to draw a direct analog because the two societies differ on so many levels. Cultural speaking, one might cite the USA and the Indian Nations, the Sioux in particular, during the Indian Wars. One was a regimented industrial powerhouse mainly focused on expansion and the other was a society focused on war and warriors.
Macedonian / Greece under Alexander and India might be another example. The Federation mirrors the Macedonian egalitarianism towards their assimilated subjects (Egyptians and Persians both fought under Alexander's banner after their nations were conquered) whereas the Indians were an alien race far removed from the Macedonian homeland with signficantly different values.
USA & USSR comparisions fall flat to me because there was not open conflict between the two powers, however the numerous proxy conflicts do mirror the neutral zone arrangement between the galatic empires. For the same reasons, the anomosity between the Japanese and the Russians could also be cited as an example. In fact, Sino-Russian conflicts do actually have a neutral zone of a few islands between the two.