Hello Mr. Grumpy!
First off, I want to thank you for not only providing excellent and prompt Tower of God translations, but you also make me smile regularly with your T/Ns and little snippets you add lol
There is a story being released right now called Red Alert. It is along the same vein as Gate: Thus the JSDF Fought There, a fantastic light novel turned manga story hosted right here on Batoto! From what I have been able to glean from it, it is very similar but taken up to epic proportions.
From what I have been able to gather,
Apparently, an evil empire that sucked all mana from their local Earth, in order to get more mana, tries summoning a land from another universe fresh with mana- and end up summoning the USSR circa 1941. Keep in mine, this "Evil Empire" is about as equipped as a medieval army..... that's not going to end very well lol
Here is the Link, they are done in text (for now) hopfully it can be adapted if it gets popular enough!
http://ncode.syosetu.com/n7498bd/
Thanks again guys!
-Anthony