Like a Noah in reverse St Patrick kicked snakes off the rain-drenched ark of Ireland. So complete was his mystical sterilization of the land that seven hundred years later in his Topographia Hibernica (1187) Gerald of Wales could write: “There are neither snakes nor adders, toads nor scorpions nor dragons… It does appear wonderful that, when anything venomous is brought there from foreign lands, it never could exist in Ireland.” Indeed, even as late as the 1950s the Irish naturalist Robert Lloyd Praeger wrote, “The belief that “venomous” animals – which term included toad, frogs, lizards, slow worms and harmless as well as poisonous snakes – did not and could not flourish in Ireland, owing to St Patrick’s ban, long held sway, and possibly is not yet extinct.” (Natural History of Ireland (1950))
Snakes, however, are not the only species that can be found in Britain or continental Europe while being entirely absent from Ireland. Moles, several species of bats, many bird species, including the Tawny Owl, several titmouse species, and woodpeckers, innumerable insects species, many plants, and so on, might be added to the roster of St Patrick bio-vandalism. Of course, biogeographers have long known that the impoverished nature of the Irish biota is attributable to a number of factors unrelated to St Patrick.
Firstly, Ireland is a relatively small island with an area of 84,421 km² compared to Great Britain which is almost three times the size (229,848 km²). The European land area is considerable larger still being over one hundred times that of Ireland’s (at 10.18 million km²). Now, one of ecology’s more robust laws posits a relationship between area and species diversity. The more land, the more species. A consideration of the relatively restricted latitudinal range of Ireland in comparison to Europe intuitively suggests why Ireland must have fewer species. For example, since Ireland does not have a considerable southern stretch it has no Mediterranean zone, though it does have an enigmatic “Lusitanian flora” found disjunctly in Ireland and in North Spain and Portugal. This includes a saxifrage commonly known as St Patrick's Cabbage, but, the component to Irish vegetation is rare indeed. Nor does Ireland have tundra habit, though, of course, it can be get chilly there at times.
Secondly, the present day biota of Ireland was assembled largely after the the glaciers of the Last Ice Age retreated. Although there may be some relicts of those formerly icy time, for example the Irish Arctic char, an apparently delicious trout-like fish, which is found in some Irish upland lakes, most Irish wildlife migrated there over the past several thousands of years.
Important to understanding these post-glacial migratory patterns is knowledge of the timing of the closing of putative land-bridges connecting Ireland and Great Britain, and Great Britain and the European mainland. Ireland was separated from a source of biotic colonists early in its post-glacial history, whereas Britain retained these connections until some time later. Naturally, species that flap, float or swim could make their way over to Ireland in their own sweet time. But snakes and other creeping things were quite simply out of luck.
St. Patrick must surely be absolved of the high crime of banishing snakes from Ireland since by that time of his mission in the 5th century there were no snakes to banish. One might wonder, therefore, how he earned his reputation as snake-killer. There are at least two interesting theories about this.
Snakes can be seen as potent symbols of the ancient faiths of Ireland. From this point of view stories of St Patrick grappling with snakes commemorates his mighty struggles to overcome Irish paganism.
Ireland in the fifth century, of course, was a Celtic society. The Celts were relative later-comers to Ireland having only arrived sometime before 300BC. The manner of their arrival is a matter of dispute: was it an intrusion or was it some combination of migration and cultural diffusion? Authorities disagree, disagreeably. The religion of the Celts in Ireland is similarly contested. It was no simple affair being composed not only of its own endogenous elements but it absorbed parts of the older traditions of the island. These traditions stretched back thousands of years to the Mesolithic monument builders and before. For example, the degree to which the human sacrifice practiced by the Druids drew the “cannibalistic feasts” engaged in by the Irish is a matter for grisly speculation. Be that as it may, there are, according to T W Rolleston’s classic Celtic Myths and Legends (1911, republished 1990), a number of distinctive features of Celtic spirituality and intellectual culture. These include adherence to popular superstition and magical observance (including human sacrifice), which largely focused on local topographic features. Underlying such observances was a philosophical creed based upon the sun as a central object of veneration. Additionally, individual personified deities, Lugh for example, oversaw the social order. [Lugh has endured a horrifying fate over the years atrophying from sun god and patron of art and craft to Lug-chorpan (little bodied Lugh) or the Leprechaun]. There was, for all of this, a reputation of learning, especially related to natural phenomena, among the Celts. Finally, the administration of religion, learning and literature was invested in the priestly caste of Druids (an order that seems to have been open to both men and women).
The role of snakes and serpents as religious symbol in Ireland is discussed in fascinating detail in Mary Condren’s The Serpent and the Goddess (1989) [a book that is shamefully out of print for its 25th anniversary]. Crudely put, the snake is a representation of the Triple Goddess in matrifocally inclined pre-Celtic culture. With the advent of the patriarchal and warrior-like Celtic people the symbol of the serpent was crushed and society was transformed. Christianity merely extended the subversion of these earliest symbols and the further ossifying of patriarchal norms. The degree to which snakes are absorbed into the religious symbolism of the druids, which would be a requirement for an argument that St Patrick’s banishment of snakes commemorates his victory of druidism, is debated. It is nevertheless pretty clear that the image of the snake was important to them. W G Moorehead in an essay from 1885 entitled Universality of Serpent-Worship wrote: “That the Druids associated the serpent and the sun with their most solemn ceremonies can hardly be doubted. The creation and the universe they represented by a serpent in a circle, sometimes by an egg (the cosmic egg) coming out of the mouth of the serpent, precisely as was done by Phoenicians and Egyptians… Their temples were circles of stones with a huge boulder in the center, thus embodying the idea of the Deity, and eternity, as the serpent in a circle, and the egg.” : (The Old Testament Student, Vol. 4, No. 5 (1885)).
It must certainly have been the case that St Patrick’s evangelism was a threat to the established order of Celtic religious life. Christianity with its seeming demotion of the here and now, and its emphasis on an afterlife, clashed with the more mundane religion that prevailed at the time, one that moreover promised a rebirth to this world rather than eternal life in another. Of course, the prestige of the Druids was also put at stake in this clash between the old and the new. In his autobiographical “Confessions” St Patrick writes of threats on his life, waylayings and other shenanigans that befell him during his ministry. Perhaps these attacks originated with local druids. But Christianity ultimately prevailed and the old order, though it persisted for a while, waned. As writer Philip Freeman wrote in his biography of St Patrick, after the Christianizing of Ireland, “[m]any [druids] seem to have barely eked out a living by concocting love potions in huts hidden away in the forest.” (St. Patrick of Ireland: A Biography (2005)).
Setting aside the detailed circumstances of St Patrick’s case, the role of hero as snake-serpent-dragon crusher is a universal one. The folklorist Alexander Haggerty Krappe connected St Patrick’s vanquishing of snakes to this tradition in which a hero rids an region of noxious vermin. For example, Herakles, the Greek hero, is associated with snakes. As a youth Herakles survived an attack by Hera, wife of Zeus, who dispatched snakes into a bedroom where our hero and his brother slept. Herakles crushed a snake with each hand and played with their corpses. Furthermore, Krappe noted that “the Erythraean established a cult of Heracles Ipoktonos ('the worm-killer'), because that god was supposed to have destroyed, on one occasion, a sort of phylloxera threatening ruin to the vines.” Since phylloxera are inconspicuous insects the term “worm-killer” refers, I suppose, to generally pestiferous creatures. From this perspective, St Patrick banished the snakes from Ireland because this is just what bad-ass heroes do.
Thus, St Patrick driving out the snakes of Ireland may indeed symbolize his donnybrook with the druids or the story may simple be the sort of universal hyperbole that hagiographers felt compelled to append to his biography. Either way, St Patrick cannot be accused of having especially meddled in the affairs of the Irish biota. That being said, St Patrick was not just an evangelist of the message of Jesus, he brought with him the culture of Romanized Britain. What happened in the fifth century Ireland was in some senses as profound an encounter between two cultures, at least in terms of ecological consequences, as was the initial clashes between settlers and the indigenous peoples of the New World more than a millennium later. The introduction of Christianity to Ireland ushered in a set of changes, many of them technical ones concerning agriculture, that radically transformed the Irish landscape. Of this clash F.H.A. Aalen and his colleagues wrote “Ireland underwent radical change from the fifth century. The pollen record testifies to a huge upsurge in grasses and weeds associated with pasture and arable farming…. A combination of factors led to a revolution in the landscape.” (Atlas of the Irish Rural Landscape. Cork University Press, Cork, Ireland 1997).
Within a few centuries after St Patrick, agriculture had greatly expanded both in the almost innumerable monastic settlements and on secular lands throughtout Ireland. The population of the island is thought to have increased as well. One way or another, Christianity resulted in a reversal of what some archaeologists refer to as an Iron Age lull, and the start of a major assault on the wilder lands of Ireland. St Patrick may be innocent of sepenticide, but the introduction of Christianity to Ireland undeniably had far ranging ecological implications for the island of Ireland.