By your own definition, last century saw overt nationalistic exceptionalism in at least Japan and Germany, also with an associated creation myth and pantheon of

By your own definition, last century saw overt nationalistic exceptionalism in at least Japan and Germany, also with an associated creation myth and pantheon of gods. Depending on how thin you want to spread it, I think there's a good case for throwing in Italy and Turkey/Ottomans and probably all the European colonial powers.