The mythological god Pan (Latin Faun) was supposed to cause sudden panic, unfounded fear and terror among people and animals with his shout. This panic (θορύβου Πανικοῦ) and confusion could lead to a castling of military units that, under the influence of fear, could misinterpret the enemy’s movements.
In the account of Diodorus Siculus, we find the following explanation:
But while they were encamped near Phylê there came a heavy snow, and when some set to work to shift their encampment, the majority of the soldiers assumed that they were taking to flight and that a hostile force was at hand; and the uproar which men call Panic struck the army and they removed their camp to another place1.
