I think this is pertaining to the 2nd location:
It's connected to World War 2
It's connected with the Enigma machine and Alan Turing
It's connected possibly with a german high-ranking naval officer
It has to do with a U-boat capture in a historical event, or a naval battle.
The Enigma machine codes were captured on a U-Boat during several operations.
Fun Fact: Beatles stayed in hamburg where is a captured russian submarine at a naval museum
Charles Babbage, Alan Turing and Alonzo Church are kinda connected in the field of cryptography, computer design device-making
There was a recent film - The Imitation Game with Benedict Cumberbatch displaying the events, maybe the OP got his inspiration watching it.
If the OP has a system with 3 different countries, and these countries are connected, the most plausible trio would be Germany-USA-England
or Russia-USA-Egland. If he means the Cold War it's probably something connected in Russia. Inspiration probably The Americans series
I might be right or dead wrong but this is what makes sense to me.
