Celtic mythology originates from the Iron Age Celts’ belief system, known for their polytheistic practices, much like other Europeans during the same era. They held a rich mythology and religious framework.
However, Celtic communities that had substantial interaction with Ancient Rome, such as the Gauls and Celtiberians, saw their mythology vanish with the rise of the Roman Empire. Their subsequent transition to Christianity, the loss of their Celtic languages, and the adoption of Latin further contributed to this.
Interestingly, the preservation of their mythology is largely attributed to Roman and Christian sources of the time. Celtic groups that retained their political or linguistic identities, like the Gaels and Brythonic tribes of the British Isles, left traces of their ancestors’ mythologies, which were eventually documented during the Middle Ages.
Despite the vast geographical reach of the Celtic world, spanning most of Western Asia, the Middle East, and Western and Central Europe, there was no political unification or significant central cultural influence. This lack of uniformity led to substantial variations in the local practices of the Celtic religion, though certain themes, such as the god Lugh, seem to have spread across the Celtic world.
Over three hundred deities’ inscriptions, often matched with their Roman equivalents, have managed to survive till today. Most of these deities appear to have been ‘genii locorum,’ translating to ‘local or tribal gods,’ and only a few enjoyed widespread worship. Nevertheless, the remnants of Celtic mythology suggest more consistency in their pantheon than commonly recognized.
The characteristics and roles of these ancient deities can be inferred from various sources, including their names, the locations of their inscriptions, their iconography, the Roman gods they are paired with, and comparable figures from subsequent Celtic mythologies.
Celtic mythology is categorized into several related subgroups, largely aligning with the branches of the Celtic languages.
Celts as Head Hunters
“Amongst the Celts, the human head was venerated above all else, since the head was to the Celt the soul, centre of the emotions as well as of life itself, a symbol of divinity and of the powers of the other-world.” – Paul Jacobsthal, Early Celtic Art.
Evidence of the Celtic fascination with the severed head is not only found in the numerous depictions in La Tene carvings but also in the surviving Celtic myths. These narratives are replete with tales of heroes and saints bearing their own decapitated heads, including the likes of Sir Gawain and the Green Knight, who, after being beheaded by Gawain, picks up his own head, mirroring St. Denis’s act of carrying his head to Montmartre’s peak. Once detached from the earthly body but still sentient, the animated head is believed to gain insight into the mythic realm.
Diodorus Siculus, in his 1st-century History, recounts the gruesome Celtic practice of head-hunting. Following a victory, they severed the heads of their fallen adversaries, tying them to their horses. These bloody trophies were entrusted to their aides and taken as spoils of war while they sang songs of triumph. These heads were hung on their homes, akin to hunting trophies.
Prominent enemies’ heads were treated with cedar oil, stored in a chest, and showcased to visitors. They took pride in turning down hefty sums of money offered for these heads, attributing such refusals to their ancestors, fathers, or themselves. Some even claimed to have rejected the head’s weight in gold. This practice, seen by them as a display of grandeur, was indeed a testament to their continued animosity towards their defeated foes.
Celts also had a belief that if an enemy’s head was fixed to a pole or fence near their dwelling, it would cry out when danger approached.
The Celts, as head-hunters, saw the severed head as a perpetual source of potent spiritual energy. If the head was indeed the soul’s seat, owning a slain enemy’s head, honorably obtained in combat, brought considerable prestige to a warrior. Tradition has it that the interred head of a deity or hero named Bran the Blessed served as Britain’s guardian against invasions across the English Channel.
The Mythology of Ireland
The most ancient collection of myths hails from early medieval manuscripts discovered in Ireland. However, it’s important to note that these were authored by Christians, resulting in a noticeable transformation of the previously divine attributes of the characters.
At the heart of these myths is a battle between two races with divine characteristics: the Tuatha Dé Danann and the Fomorians. This conflict serves as the foundation for the text, Cath Maige Tuireadh (the Battle of Mag Tuireadh). Parts of this narrative are also found in the historically oriented Lebor Gabála Érenn (the Book of Invasions). The Tuatha Dé Danann were symbolic of different facets of human society, encompassing kingship, craftsmanship, and warfare, while the Fomorians embodied chaos and the untamed aspects of nature.
It appears that the paramount deity of the Irish pantheon was The Dagda.
The Morrígan, an ancient Irish Celtic goddess of war, was known to embody three aspects. While collectively referred to as the Morrígan, her divisions, embodying diverse elements of battle, were known by different names such as Nemhain, Macha, and Badb, along with other less common names.
The extensive prevalence of the god Lugus, who is seemingly linked to the mythological character Lugh in Irish tradition, is evident in the numerous place names featuring his moniker, which span the Celtic world from Ireland to Gaul.
The pantheon also includes goddesses like Brigid (or Brigit), the Dagda’s daughter; nature deities like Tailtiu and Macha; Epona, the goddess of horses; and Ériu. The male deities comprise Goibniu, the god of blacksmithing and eternal brewer of beer, and Angus Og, the god of love.
The Mythology of Wales
Our understanding of the pre-Christian mythologies of Britain is less comprehensive than that of Ireland. Notable elements of British mythology are seen in the Four Branches of The Mabinogi, particularly in the names of several characters such as Rhiannon (‘the Divine Queen’), Teyrnon (‘the Divine King’), and Bendigeidfran (‘Bran [Crow] the Blessed’).
It’s highly probable that other characters originate from mythological sources. Furthermore, various episodes, like the arrival of Arawn, an Otherworld king who seeks a mortal’s assistance in his disputes, and the story of a hero who can only be slain under paradoxical circumstances, can be linked to broader Indo-European myths and legends.
Significant figures include the children of Llŷr (‘Sea’, equivalent to the Irish Lir) in the Second and Third Branches, and the children of Dôn (known as Danu in Irish and earlier Indo-European traditions) in the Fourth Branch. However, the stories themselves aren’t primary mythology.
Gaulish and other Mythology
The mythology of the Gauls, also known as Gaulish mythology, is a branch of ancient Celtic mythology associated with the Gauls, who inhabited regions in Europe that are now part of modern France, Belgium, Switzerland, and areas of the Balkans. Unfortunately, our understanding of Gaulish mythology is quite limited due to a lack of surviving literature and the historical suppression of Gaulish culture and language following the Roman conquest.
Unlike Irish or Welsh mythology, which were preserved in medieval texts, much of what we know about Gaulish mythology comes from Roman commentaries, archaeological evidence, and inscriptions. These sources suggest the Gauls practiced a polytheistic religion with a pantheon of deities related to various aspects of life and nature. Some of the best-known Gaulish gods include the sky god Taranis, the horned god Cernunnos associated with animals and fertility, and the mother goddess Epona.
Despite the scarcity of direct information, the Gauls’ mythological beliefs seem to have shared common features with other Celtic cultures, such as a belief in the Otherworld, a realm of deities and spirits, and reverence for natural features like springs, forests, and rivers.
It’s important to note that much of Gaulish mythology remains speculative due to the limited and fragmented nature of the sources.
Caesar on Celtic Mythology
A classic reference to the Celtic gods of Gaul can be found in Julius Caesar’s “Commentarii de bello Gallico” (52-51 B.C; The Gallic War), where he enumerates the five primary gods worshipped in Gaul. However, he uses the names of the corresponding Roman deities, as was customary during his time, and outlines their roles.
Mercury, according to Caesar, was the most honored of all gods, with numerous depictions found across Gaul. This deity was regarded as the initiator of all arts (and is often identified with Lugus for this reason), the protector of explorers and merchants, and the most influential deity in terms of commerce and gain.
The Gauls also venerated Apollo, Mars, Jupiter, and Minerva. Caesar describes the roles of these gods in a manner similar to their perception in other societies:
Apollo was the healer,
Minerva, the promoter of crafts,
Jupiter, the ruler of the heavens, and
Mars, the controller of war.
Caesar adds that the Gauls considered Dis Pater, a Roman and Celtic god of the underworld later associated with Pluto or Hades, as their ancestral figure.
However, it’s important to note that Caesar, reflecting his Roman perspective, does not refer to these gods by their Celtic names but uses the names of the equivalent Roman deities. This practice considerably complicates the task of connecting these Gaulish gods with their original names in the Celtic mythologies.