For some reason, I seem to get it a lot simply fighting rebels in Italy with my general, but those were against the odds.

My current "kill everybody who gets in your way but be chivalrous and have the odds be against him or be even all the time" general has had the Imperator trait about 4 or 5 times already. Bah, I stopped going to get the triumph in Rome after about 3 or 4 times. I simply just fought battles, as I described ever so succinctly earlier, with the odds against me or even with large amounts of troops. Imperator trait came along after a couple battles.