Last time I talked about the lore we learned in Fischl's Domain that might have just told us everything we needed to know about the destroyed kingdom of Immernachtreich.
Ok but where is the Immernachtreich? I once said that the Chinese for Immernachtreich meant it was actually more like a separate plane for example Ei's Plane of Euthymia. But this quest states it as your typical region where Amy gathered her people and kept them safe.
Well as it turns out both the Tasraque thing and one of Fischl's own lines during the event might have given it away. Question: Why does nobody in Genshin Germany understand Fischl? She's using German words right? They should be able to understand her just fine. Well what if she's not actually speaking "German?" Yes she's speaking German but just hear me out. 
The fact that we don't have a German dub of this game so everybody in Genshin Germany is speaking English and even Fischl mispronounces her German words makes me think that if we were to shift everything over to a German dub then all the English would be German so the German wouldn't be. It's like the old saying goes "it's all Greek to me." But what if you are Greek? So I looked at the history again and wouldn't you know it-
Germany has had a really colorful history. Yes Mondstadt is based on the Holy Roman Empire but the Holy Roman Empire is not modern day Germany. Back on day 1 of this quest Fischl says something that I pointed out could be a thing in Mondstadt but wasn't part of Medieval Germany.
What if the Immernachtreich is based on Prussia? It's Germany adjacent and they speak a totally different language more Baltic which is related more to Russian than Germanic. So look at that map. Prussia is all the way at the northwest part of what is now Germany. Further east would actually be Russia. Based on the timeline the Immernachtreich might have formed around when Venti was usurping Decarabian and moving the people to New Mondstadt.
From the lore we know that when he moved them he first had to reshape the area by drowning Pilos Peak and cutting off the tops of some mountains which became the Golden Apple Archipelago. But these feats seem just a little out of his pay grade considering how weak he is when we actually see him. And we also know he co-ruled Mondstadt with Istaroth back then. In the event we learn that Amy too also shaped the Immernachtreich by carving out mountains and oceans. What if Venti didn't shape Mondstadt on his own but was helped by these two stronger gods?
If we think about it that way maybe Immernachtreich was a place in between Mondstadt and Snezhnaya until it was razed by Phanes. It represents Prussia in Teyvat and would eventually be absorbed into Mondstadt which represents Germany just like the real Prussia is now part Germany part Poland. (which used to be a part of Russia) This would be similar to what happened with Havria and the tribe of the Chasm in Liyue.
The close proximity also means that after Amy was defeated and diminished it wouldn't be that hard for her to end up in Mondstadt and become a human. Maybe the disembodied Naberius even helped guide her there before eventually reintroducing himself to her in the library.
What do you guys think? Could this have been the story? Could this be where the Immernachtreich was? And how might this history play into the stories and prophecies about Fischl?
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