" Ariovistus did not come to an engagement, he discovered this to be the reason--that among the Germans it was the custom for their matrons to pronounce from lots and divination whether it were expedient that the battle should be engaged in or not; that they had said, "that it was not the will of heaven that the Germans should conquer, if they engaged in battle before the new moon. "

― Gaius Julius Caesar , The Conquest of Gaul