What country was the first to make Christianity its official religion? What year was it in?
I can only guess, but I’d say it was the Roman Empire when the Emperor Constantine legalized Christianity with his Edict of Milan in A.D. 313. Christianity was adopted as the official religion of the Roman Empire by the Emperor Theodosius in A.D. 380. As I said, this is only a guess. You may wish to consult with a research librarian to see if there are earlier contenders for the honor.