Relief showing the god Esus, from the Pillar of the Boatmen, dedicated to emperor Tiberius in 14 A.D. by the sailors of the Seine River in the city of Lutetia (now Paris). Now it is housed in the National Middle Ages Museum (Musée National du Moyen Âge, Thermes et Hôtel de Cluny), Paris.
Esus was a Gaulish divinity on whom only scant information is available. The Roman poet Lucanus described this god as “awesome”, on whose “ruthless altars” human victims were sacrificed (Pharsalia, I, 444-446). Other Latin sources identify this deity sometimes with Mercury, sometimes with Mars, suggesting his role as protector of merchants (and perhaps associated with the world of the dead) and of warriors. The picture shows him in the act of felling trees, and this probably indicates that he was regarded as a god of vegetation and woodlands, whose power was manifested in the great trees in the woods, of which he promoted the growth and might. The etymology of his name could perhaps be brought back to the term *vesos-, “the best, excellent”, which recalls the epithet of the Irish god Dagda, the “good god”, divinity of abundance, of magical power and of war, who was furthermore one of the lords of the Underworld.

[Image: http://commons.wikimedia.org/wiki/File:Le_Pilier_des_Nautes_03.JPG]