The Milk Drinking Serpent

Out on a Spring jog last weekend I was delighted to encounter a grass snake which I chased into a corner where I could admire it. They are very lucky in the folklore of Indo-European countries and this must be due to its former mythological status. The grass snake (natrix natrix) is a non-venomous serpent found across Europe and the Eurasian steppes where the Proto-Indo-Europeans originated.

A paper by Lender and Janssen (2014) argued that the grass snake has been sacred since the Neolithic, and owes its wide distribution due to the fact that dung heaps made by farmers create the perfect nesting environment for them to thrive. The paper shows that the grass snake spread during the Neolithic with agriculture. We can presume it spread even more in the late Neolithic, after the Indo-Europeans brought lactase persistence to the region and made cows an even more valuable resource.

Snakes got a bad name with Christianity, and the grass snake lost its special status in many places. However, in Lithuania, the last European country to be Christianised, the grass snake, known as žaltys, is still a sacred animal. In mythology, it is a household spirit, and Baltic people, particularly young couples, would keep them as pets beneath the bed, and feed them by hand. If a grass snake was found in the wild then people would try to befriend it with an offering  of milk.

Found a snek at the lek #donttreadonme #grasssnake #reptiles #steveirwin

A post shared by Survive the Jive (@survivethejive) on May 27, 2017 at 8:59am PDT

I am assured by a Swedish friend that the same practice of offering bowls of milk to grass snakes, snok, also occurred in Sweden until quite recently. This got me wondering how widespread the practice was. 

Then I read in the Hindu myth of Mansā Devi, the goddess of snakes, the story of a girl called Behula who placated malicious serpents with bowls of milk to drink. The snakes were vicious in the legend but the snake goddess is revered and she can heal or prevent snake bites. In fact, there is even a Hindu snake festival held in July/August called Naga Panchami, during which snake spirits (Naga) are worshiped. Just as the realm of the underworld in Norse mythology is populated by serpents such as Nidhogg, Hindu cosmology relegates Naga to the lowest of the seven realms of the universe. During this festival, snakes are sometimes bathed in milk or they are fed milk, but as you can see from the image below, the snakes are reluctant to participate. Some Indians don't realise that snakes prefer bugs and rats to bowls of milk.

The notion of malevolent spirits such as elves or fairies or even animals such as hares stealing butter or milk is common in the folklore of the British Isles, but in rural parts of England, such as Gloucestershire, there are specific examples where milk is said to be sucked directly from the cow's udder by a snake. This charming tale from 1700 is a nice example:

The story begins with the unaccountable failure of an Alderney cow to yield her customary supply of milk. Hitherto the reputation of Daisy, the animal in question, had been above reproach. She had borne twelve promising calves in thirteen years, and had supplied milk with the regularity of penny-in-the-slot machine. But without warning her generous fountains ran suddenly dry, and to quote ‘our Jarge’ my principal informant ‘Her didn’t yield not spot of milk for more’n two days.’ The farm bailiff, suspecting that gipsies or tramps must have got at Daisy’s supply, instructed the cowman to keep an eye on that excellent beast, which Jorge accordingly did, with surprising results. After a brief period of vigilance the honest fellow sought out the bailiff and made his report boldly as follows; ‘l’ve been a-waitin’, and I do know what be wrong with our Daisy. I’ve seed snakes.’ Now the farm hand who sees snakes is rarely encouraged. ‘Jarge,’ however, stuck manfully to his story, which was that had come upon Daisy lying on the grass with expression of bovine bliss upon her countenance ‘same if her bein’ tickled pleasantlike.’ He made the cow get up, and then to his astonishment saw two great snakes wriggle in the grass where she had lain. ‘I struck out stick’ quoth Jarge ‘and killed ’em dead. They’ve been a-suckin’ our Daisy’s milk this three days.’

In Spain, rural peasants not only still believe that snakes will steal the milk of their cows, but also that a sickly child may be suffering because a snake has been stealing the mother's milk straight from the tit while she sleeps. The Spaniards are wont to kill snakes wherever they see them. No doubt due to Christian superstition and ignorant prejudice. The snake in these folkloric beliefs is reduced to a despised thief (maybe due to Christianity), unlike the revered serpents in the other examples, but in each case, the enduring belief that snakes drink milk must derive from some pre-Christian, Indo-European source.

Snakes, being reptiles, do not have the necessary digestive equipment to break down the lactose in milk and therefore have no interest in drinking it. In fact, even human adults couldn't digest milk until the Indo-Europeans spread their lactase persistent genes across Eurasia in the Bronze age. The Indo-Europeans had a prominent serpent in their mythology which was slain by the storm god. They also had a myth about enchanted apples being stolen from a deity by a sub-race of god-like beings. It seems likely that there was a folk belief among these early drinkers of cow and goat milk, that their treasured nutritious beverage would be stolen from them by serpents and that serpent-like nature-spirits ought also to be placated with offerings of milk.

EDIT: There is a whole paper on this phenomenon here - ERMACORA (2017)
EDIT 2019: There is also an Austrian folk story about a milk drinking grass snake. See video below.