The question in OP allows for some interpretation. Even if there was a crater formed in 1178, I doubt Ceasar would be shocked by the appearance of the present-day moon. So I am trying to think of what could be recognized as different by a keen observer (yes, fuzzy definitions, but history is full of dudes that stare into the sky and see things, so imagine one of those characters).

But you can see some "texture" on the moon surface. Especially when the moon is about one week after new moon, it is not yet that bright that you only see a bright disk in the night sky. This assumes you are in a relatively dark place to begin with, so far from a city, and that the sky is clear. Even then, the craters have to be pretty large to be observable as pattern, hence the many small craters that form are irrelevant even to the keen observer I imagined.