Strictly speaking “Russia” is Muscovy restoring “Kyivan Rus”. I don’t disagree that “Kyivan Rus” as a nineteenth century historiographical term would be a silly formable country to add to EUIV. My observation is just that Yuan, Mongol Empire, Latin Empire and Roman Empire are also silly historiographical terms, as is Rum really, and that hasn’t stopped them going in. No one was working to restore any of those countries because in most cases there wasn’t anything to restore. Yuan is the name of a dynastic period, for heaven’s sake. “Latin Empire” is a historiographical term for a moment in Byzantine governmental history. “Mongol Empire” is just a general term for a period when a state on the EUIV map got really big. There are worse formables than Kyivan Rus already in EUIV, the “let’s keep it vaguely plausible” battle is long lost. Might as well add Carthage, too.
I did some research and apperantly "Ruthenia" was used as a name to represent any orthodox russian state in the region of Kievan Rus. So for all purposes, Ruthenia alone covers all cases from a certain perspective. Thats from wikipedia so take it with a grain of salt.
Ruthenia[a] is an exonym, originally used in Medieval Latin as one of several terms for Kievan Rus', the Kingdom of Galicia-Volhynia and, after their collapse, for East Slavic and Eastern Orthodox regions of the Grand Duchy of Lithuania and the Kingdom of Poland, corresponding to what is now Ukraine and Belarus.
If this holds true, any topic on Kievan Rus (regarding unique formable etc) is just hollow.
Russia,
at the start of EU IV (very important to separate the historical setting from modern day), was the name for the lands of the Rus people, the people of the Kievan/Kyivan Rus, from Halych to Novgorod, and Polotsk to Suzdal. Muscovy = Russia is false at the start of EU IV, at the time all were Rus people. After the Tsardom of Russia took over most Rus land they started to impose their specific regional sub-culture (Muscovite) onto the others. This led to anti-Russian sentiment in what we now call Belarus and Ukraine, and the creation of their own national identities which we know today. This is similar to Germany and Spain, where many sub-cultures eventually unified but due to history and politics there are some standouts, this case Austria and Portugal. Rus was just the name for the people, they didn't call themselves East Slavic, Ukrainian, Belarusian, or even Russian, you were Rus. That is how we got Russia as a name, Rus (the people) and sia (land of), the land of the Rus. This is a trend across the entire English language due to Latin influence.
Now Ruthenia is just Russia but in Latin, think of it how different languages have different names for countries. In English we say Japan, but in Japanese they say Nihon, in Russian it's Yaponiya, and Chinese it's Riben. The inherent struggle between the names Russia and Ruthenia is religious, the fight between the Roman Catholic Church and the Orthodox Catholic Church. It's especially important to remember that at this time religious identity was drastically way more important than ethnic identity. It wasn't Moscow vs Kiev/Kyiv, but loyalty to which Christian branch, which at the time it was near universal for the Rus to follow Constantinople. Now things got complicated during the 15th century with the schism between Moscow and Constantinople, which eventually led to Moscow taking up the mantle of being the "Third Rome" and preserving true Christianity under Orthodoxy. But there were also attempts to spread Roman Catholicism to the Rus, both by locals and by the West. There was Daniel of Galicia which was crowned by the Pope as "Rex Rusiae" or in English the King of Russia after he promised to switch allegiance to Rome. Polish kings declared themselves the Lord of Ruthenia after carving up the Kingdom of Ruthenia with Lithuania. And the last main efforts by the Commonwealth, the Union of Brest which created an autonomous Eastern Catholic church, the Ruthenian Uniate Church, and the possible creation of a "Grand Duchy of Ruthenia" (though Belarus was excluded from it due to Lithuanian control and centralisation, and to avoid crippling Vilnius too much).
This is why I say only Russia and Ruthenia are the only formables that make sense, they are the modern versions (at the time) of a remade Kievan/Kyivan Rus that has defeated its foreign conquerors and united the people once more. However, Ruthenia should be for a Catholic version and Russia should be for an Orthodox version. We like to view Russia as just an extension of Moscow because that's what happened in our history. But with how EU IV is, being a historical sandbox, other East Slavic states could rise up and proclaim a new empire, especially since arguably there should be a Kiev/Kyiv state at the start of the game and possibly other principalities. Heck, even if we looked at the modern day Russia only, a Novgorod Russia would be radically different than the standard Moscow Russia, hence why PDX is changing up Russia next update. Ruthenian is not an exclusive Ukrainian term, nor is Rus an exclusively Russian term. The usage of Ruthenian = Ukrainian is a modern historical development, even during WWI most Ukrainians still declared themselves Rus due to Orthodox faith and opposition to the Latin Church. Both tags represent the same core thing, a united East Slavic Empire, but the names are different due to religion. Ideally the game would have more events and missions on the period and religious back and forth between Rome and Moscow on the region, it was quite disappointing to see nothing in Lions of the North on the issue. The Union of Brest in particular was shocking to see neglected considering how big that was, there's nothing on converting the land to Catholicism, instead you just become mega tolerant PLC and grant autonomy through estate privileges. There was nothing on the Cossacks struggle against Warsaw, nothing on the PLRC, or anything else, it's all just ignored sadly.
Now regarding the other empire tags, I fail to see how they are an issue.
- Mongol Empire isn't perfect but it's better than Great Nation, not to mention there were plenty of Mongol hordes still so one trying to reunite the old Khaganate isn't entirely crazy, just unlikely due to Russian conquest
- Yuan is a dynasty name so it's not perfect either, however the Yuan family still continued a presence in Chinese politics, it's also hard to guess what name another Mongol family would create for their rule over China, Yuan is the best we have to work with
- I do not like Latin Empire either, but just because there is one stupid name doesn't mean we should add more
- While the restoration of the old Roman Empire is crazy, the proclamation of a new Roman empire is not that far fetched, Europe's history is dotted with many champions trying to recreate their continental dominance, it's a nice reward tag for anyone who can pull it off, I just think the tag needs reworking to move away from being the literal Roman Empire from a millennia ago somehow coming back to life and more a united European empire
- I don't see the issue though with allowing the restoration of the Sultanate of Rum, just because the Ottomans chose not to doesn't mean all the other Anatolian beyliks wouldn't have either, those beyliks were the successors to Rum, makes sense that if another rose up and crushed the Ottomans and conquered Anatolia they would claim to be the new Sultan of Rum, the tag just needs to be fleshed out to be different from the Ottomans instead of just being a different colour with inferior ideas
