Historical guess:
the Klingon empire-the Japanese Empire
the United Federation of Planets-USA

The first series depict the world war two,conflagration between americans and japanese,(with the proper comical cultural aspects),then they become allies

the Cardassian Union-Soviet Union,new enemy of the Federation,they are quikly ran over by the Dominion(red dominion-communism) ,who occupies a larger portion of the map(delta quadrant) than the Federation.Ferengi are the smallest "country" ,followed by Romulans and Klingons.
However,after the Cardassians are ransacked by communism ,the Federation does not consider them a threat ,much like Russia after 1989.

the Ferengi Alliance-the Jewish alliance,seek to profit from all trades and wars between civilisations

and finally....ready?
The Romulan Star Empire-The Romanian Star Empire,cloaking device,cultural aspects,;language,secret police,military,the Senate ,the Praetor,the secrecy ,it all fills in.

BTW:I only play the Romulans in ST:BOTF