Raiki
Warlord
Wu Zetian
e: we aren't really sure how the exact mechanics of espionage work. For all we could know, its that that civ who told Wu is the only civ with spies (thanks to being way ahead of everyone else in tech) and it doesn't take Gandhi to put 2 + 2 to get 5.
I thought that when the first person entered Renaissance, everyone got a spy. Therefore, it's impossible for only one civ to have spies.
~R~