Prussia, Russia, Sweden, England, the Ottoman Empire...just not a lot of big European nations left to choose from, neh?
I'll go with something no one has ever heard of. That way, I can make up almost anything without sounding too crazy!
Nation: The Republic of Genoa
Bio: Zaroff's father was a banker who managed to pull strings to get his son into a good position in the Genoan military. Annoyed with the way others treated him, Zaroff showed that he could, in fact, lead soldiers quite well, thank you not at all. He managed to climb through the ranks to the top, displaying ingenuity and a general disregard for morons along the way. This latter gave him excellent politicking skills which, in another world would serve him well in a few decades, after the Genoan military was disbanded and he entered the world of politics. In this one...who knows? He'll likely either be dead or a war hero by this war's end; either makes political skill a bit less relevant.
Traits: Ingenuity, Politicking