This illustration, dating to 1882, shows a Druid priest. Druids were an ancient Celtic order of priests and diviners. Julius Caesar mentions Druids when speaking of his conquest of Gaul in the 50s B.C. Another Roman author also mentioned Druids, and spoke of a Druidic ceremony in which a priest adorned in a white robe climed an oak tree and cut down a branch with mistletoe with a "golden sickle.".