"... angry passion yields to wisdom and Ares stands in awe of the Muses"

 "Not only during peacetime but also in war, the Gauls obey with great care these Druids and singing poets, both friend and enemy alike. Often when the two armies have come together with swords drawn these men have stepped between the battle-lines and stopped the conflict, as if they held wild animals spell-bound. Thus even among the most brutal barbarians angry passion yields to wisdom and Ares stands in awe of the Muses."

~ Diodorus Siculus (fl. c. 60-c. 30 BC)
Bibliotheca Historica, Book V.31