Esus (Aisunertos, Esunertos, Aisus, Aesus, Hesus) is a Gaulish god known from Gaulish and North African inscriptions. The most important image of this deity is that of a man chopping down a willow tree. He may be the tutelary deity of the Esuvii tribe of Gaul. Esus may be a god of the Celtic otherworld.

Esus is a deity known from Gaulish and North African inscriptions and iconography. As Aesus this deity is known from an inscription now in Florence, Italy. He is also known from the writings of the Roman poet, Lucan.

He is best attested on a large decorated pillar bearing his name, the so-called ‘Sailors’ Pillar’, dedicated to Jupiter that was discovered beneath the church of Notre Dame, Paris in 1711 (CIL XIII 03026). This being the image that is used for the representation on this page. This depicts a muscular, bearded, man chopping at what has been interpreted as being be a willow tree. Above the tree we have an image of the Tarvostrigaranus the so-called ‘Bull with three cranes’. The scene may relate to a long-lost mythology though it is now almost impossible to interpret though similar iconography appears on a stone found at Trier. A dedication to Esus has also been found at Chercel in modern-day Algeria (AE 1985, 934). In Pfalsbourg, Germany (CIL XIII 1164) he is invoked as Mercurio Esuner(to) (Mighty Esus, Mercury) indicating that Esus may share some of Roman Mercury’s attributes.

In classical writing Esus was mentioned by the Roman poet, Lucan, (M. Annaeus Lucanus) in the first book of his Pharsalia (Civil War) where he also mentions the Gaulish deity, Teutates.

Teutates horrensque feris altaribus Esus

et Taranis Scythicae non mitior ara Dianae.

uos quoque, qui fortes animas belloque peremptas

Savage Teutates, Esus’ bloody shrines
and Taranis’ altar, cruel as those
loved by Diana, whom the Scythians serve;
All these destroyed in war

According to the Berne Scholia commentary on Lucan Esus’ victims were sacrificed by being tied to a tree and then stabbed; the direction in which the blood flowed being used in augury. Though Esus has been equated with the Greco-Roman deities Jupiter, Mercury and Apollo, a strict classical parallel is difficult. Instead, French folklorist Jean Markale identifies Esus instead with a type of god–the “horrible” sky god of magic, like Odin (whose victims were also tied to a tree and flailed), Math ap Mathonwy/Gwydion (lords of magic), and Uranus. To this list I would also add Lleu Llaw Gyffes who was sacrified to the world-oak.

Esus’ name probably represents a Romanization of an original form that was probably something like *Aisus, derived from the proto-Celtic *wesu- (excellent, noble) thus Esus’ name contains the connotations of ‘respect’ (which masy make his name equivalent to that of the Germainc Woden/Odin — “The Respected One”). The deity Esunertus/*Aisunertos is also probably a variation on Esus with the termination nerto- (strength, power) appended. Thus the name becomes “strong Esus” or, in full, “The Strong Respected One”. This form of the name is known from Pfalsbourg in Germany [CIL XIII 11644] where the god is conflated with Roman Mercury by Interpretato Romana.

The link between the Tarvostrigaranus and the tree that Esus is chopping is supplied by their ecological relationship for the birds (which are actually egrets and not ‘cranes’) will perch on the backs of cattle to divest them of ticks and lice and they also nest in willow trees, which has been identified as the tree that Esus is chopping down. In Celtic mythology the ‘crane’ form is one exclusively taken by female deities; deities, moreover, who are generally associated with the other-world. Which would suggest that Esus is an archetype deity probably associated with a triple otherworld goddess. Now whether this was in martial aspect, corresponding to Mars or in healing aspect corresponding to Mercury can not be known. Though these two principles are not entirely incompatible. There is also the questin of why Esus is chopping or pruning the tree unless this is something to do with the death/rebirth of the tree itself, echoing the death and rebirth of the victims sacrificed to it. It should also be noted that the willow is a significant tree in that it stands at the intersitces betweeen realms ie it grows in marshland standing between land and water.

The similarity between the name of Esuvius and that of the Esuvii tribe of northwestern Gaul (modern Calvados) has led to the speculation that he might be the tutelary deity of this tribe.