Only a country with a comedic tradition of using perpetually struggling characters as main protagonists was able to produce a comedy series (or season thereof) about the trench war in 1916/1917. And even if others would (or could), they would hardly produce such a series finale. The entire conflict left very different marks around the world.
To be honest, I think the war is overshadowed by its 2nd edition in Germany. I wouldn't be surprised if the majority of working-age Germans didn't know more about the First World War than that there has to have been one since there was a Second World War, after all.
(The character at the beginning is called "Captain Darling", and the Blackadder character mocked this perfumed prince by calling him "darling" only during the entire season.)