"The war is between the Germans' Holy Roman Empire and the Romanian Empire for the successor of Rome to claim the papacy and with Romania having finished merging with Naples and Sicily, it is about to begin. "
The Romanian Empire, a name for the Empire centered on Byzantium now ruled by a dynasty that originated in Wallachia, ruled the east, all the way to the Danube and above, with the Hungarian city of Buda being the HRE's eastern bastion. The Holy Roman Empire, ruling the Germanies, the Low Countries, Denmark and large parts of France (the rest in the hands of the English Crown) and northern Italy. The Kingdom of the Two Sicilies had been independent, but a strategic marriage into the Romanian Imperial family saw Naples and Sicily be added to the Empire.
The HRE couldn't stand for having Romanian troops so close to Rome, and so declared war in 1700 on the basis of the Duke of Milan's tenuous claim to the Neapolitian Throne, though everyone knew that that was merely an excuse for the great power showdown everyone had known was coming for decades.
The resulting War of the Neapolitan Succession would see the HRE victorious in the Italian Theater, but pushed entirely out of Hungary and forced all the way back to Vienna. The Opportunistic English took Marseille from the HRE, but in turn, the HRE was able to bribe the Sultanate of Antioch, a powerful Muslim state ruling Syria and the Levant, to invade Armenia, distracting the Romanians.
In the Peace of Bern, signed in 1717, a large chunk of northern Naples was carved off as the Grand Duchy of Capua, and given to the son of the now late Duke of Milan who had had the tenuous claim, the Syrians got half of Armenia, the British got to keep Marsielle and the Romanians got to add the rest of Hungary to their domain.
All the war really did is leave everyone in debt and angry, and they'd have three more wars between 1717 and the English Revolution in 1813 (which ushered in a 15 year cycle of wars that saw the Romanians and the HRE on the same side)
Let me get this straight. You lost 17,000 men, and all you managed to capture was the King's second cousin!? His SECOND! COUSIN!?