The Story of Bog Butter. By John Dolan

Bog butters are large white or yellow waxy deposits regularly discovered within the peat bogs of Ireland and Scotland. They represent an extraordinary survival of prehistoric and later agricultural products, comprising the largest deposits of fat found anywhere in nature. Often found in wooden containers or wrapped in animal bladders, they are considered to have been buried intentionally by past farming communities. While previous analysis has determined that Irish bog butters derive from dairy fat, their precise characterisation could not be achieved due to chemical compositional alterations during burial in subsequent years. They generally produce a distinctive, pungent and offensive smell.

The largest Irish example weighed 23kg (50lbs) from a find in the Galtee Mountains in 1826.  Bog Butter is primarily held in the National Museum with some held by local museums.

Studying Bog Butter.

Dairying was established during the Neolithic period in Ireland, farming became established leading to surpluses in crops and other farming outputs including milk.  Milk was an important food source.  Both Old and Middle Irish sources mention butter and it appears to have been considered a high-status luxury food that could only be given to you depending on your status – Kevin Danaher (1969)

Artefacts buried in the past in Ireland has been much studied, particularly hoards of precious metals, bodies, weapons etc.

A sketch by W. S. Trench of bog butter discovered during drainage works near Geashill in 1859. (Courtesy Offaly County Council Heritage Office/Digby Irish Estates. )

Antiquarians including Sir William Wilde wrote reports about bog butter finds that were read at the Proceedings of the Royal Irish Academy.  The standard for recording these finds was relevant for the times but lacks the methodologies or technologies available to today’s researchers.

The earliest documented account about bog butter is from Sir William Petty where he describes in 1672 ‘sour butter, eaten by the peasantry and poor people in winter, may be preserved for more than twenty years’.  Around the same time Dinely, wrote in 1681, about butter layed-up in wicker baskets, mixed with a sort of garlick and buried for some time in a bog to make provision of a high taste for Lent’. 

Many of the early studies focused on the containers, later research examined the contents assisted by improving scientific tools and dating techniques.

However, three recent scientifically based papers have increased our understanding of both the containers and the contents of the bog butter.

How many have been found?

Prof. Joseph Raftery thought there were 40 examples in Ireland in the 1940s, this increased through the Earwood study in 1997 to 229 while Jessica Smith’s paper in 2019 researched approximately 500 samples in Ireland and Scotland.  A local contact has said that Bord na Mona workers regularly threw them ‘into the ditch’ rather than have delays by contacting management or the National Museum.

Earwood paper of 1997.  Note: no finds in this source from Cork, Waterford or Wexford.

Container types.

The Earwood study of 143 samples out of 220 revealed that ‘about one third of bog butter was not in any container, 12 were in baskets, 10 were in bladders, 5 were in skins, 6 were in bowls, 1 was in a box, 4 were in dishes, 4 were in troughs and about four were covered in bark’. The remainder were in wooden containers of different types. The most common wood was alder. There were many different handle styles, some kegs were for carrying, others (methers) were for drinking from, the ones with lower down handles were for carrying.  Handle styles changed over time.  Some had lids, others did not.  A sizeable number had art carved on them.

There were two approaches to making the wooden containers – the use of staves, similar to barrels and by hollowing out the centre of a piece of wood.  The production of the containers was similar to those used every day on local farms. There is no difference between those in regular use for normal butter production and storage and those used to contain the butter found in bogs. However, what is noticeable is that a number were covered in art and then buried.

Deposition, why were they buried?

Putting valuable items into the ground, rivers or bogs has been much studied in Ireland.  Items deposited date back thousands of years and include many ritual hoards – gold, silver, weapons, bog bodies etc.  Silver, particularly hack silver from Viking times may well have been buried for safety reasons.

Some authors suggested that the butter was buried as a ritual.  However, it was assumed from the earliest accounts that bog butter was placed in the ground to preserve the butter by keeping it cool. The acidic, low-oxygen water qualities of bog would have prevented mould growth.  Scientific study reveals that this butter would have become inedible in a matter of two years.

It is also obvious from the Brehon laws that butter was used to pay the local tax (cáin) from the tenant farmer to the local king in prehistoric times.  Butter was also used as food-rent as this example of ‘yearlie twenty fower methers of butter, and fiftie methers of barlie’ was exacted by Lisgole Abbey, Co. Fermanagh in 1609.  Keeping the butter secure until rent time may have resulted in burial.

The Middle Ages in Ireland were troubled times so butter may have been buried for security and supply reasons.  It is possible that butter may also have been buried in marshy ground as votive offerings that later became bog.  Several post-Medieval accounts mention storage for later consumption, the location being subsequently forgotten.  Clearly, there were many reasons why the butter was buried over 3,500 years stretch.

The butter was packed into its container which was sometimes lined around with vegetable fibres such as sedge, grass and moss.  The butter fat gained considerable flavour from its surroundings.

How old are they?

There has been much debate on why they were buried or how old they are.  In the Earwood study the oldest wood dated produced a radiocarbon date of 1802 BP or 140 AD.  Similar early date estimates from Downey and Kelly (2006) suggested the earliest dendrochronology dates were at the beginning of the Iron Age e.g. about 500BC.  The early research accepted that the earliest burial dates were from the Iron Age.

However, the Smyth and Sikora study (2019) pushes this back to earlier times. The study reveals a remarkably long-lived tradition of deposition and possible curation spanning at least 3500 years, from the Early Bronze Age (c. 1700 BC) to the 17th century AD. The oldest tested sample came from Ballindown, Drinagh, Esker Mor and Knockdrin bogs in Co. Offaly, producing a date of 1745-1635BC.  This is one of a cluster of 4 deposits from Co. Offaly and 1 from Co. Westmeath that give Bronze Age dates.  This is conclusively established via an extensive suite of both bulk and compound-specific radiocarbon dating.

What’s in the Butter?

It is clear that bog butter was not salted prior to burial, perhaps the preservation qualities of salt were not known in the Bronze Age in Ireland; it was well understood at the time of the most recent burials. Long emersion in bog has led to chemical modification.  Using compound-specific stable isotope analysis, the Smyth/Sikora study of 32 examples from the National Museum provides the first conclusive evidence of a dairy fat origin for the Irish bog butter tradition, which differs from bog butter traditions observed elsewhere.  It is not tallow or other fat product.

Dairy folklore

Eastern folklore suggests that butter was first made by nomadic tribesmen from Central Asia carrying milk in leather saddle bags and was transformed by regular galloping across the deserts. The advent of cows and dairying came to Ireland with the arrival of Neolithic peoples around 6,000BC.

The rituals about milking, the uses of milk and the production of butter have been handed down in the rich archives of our oral literature.  The value of milk and the need to protect its production and processing into butter are well recorded in the Main Manuscript Collection, but particularly the Schools Collection held in the National Folklore Collection at UCD, Dublin.

Selling home made butter today in the absence of the bog variety! Excellent quality this one.

Here are some examples:

‘The butter could only be taken from certain people. I was told the following story. A man and his wife were churning one day. A stranger came in to put a coal on his pipe. The stranger never spoke from he came in until he went out. The man and woman were churning for five hours and never a bit of butter came on the churn. They had to give the milk to the calves and pigs.’ (NFC Peadar O Coigligh, Colehill, Longford)

‘When a cow calves first it is right to milk the first four drops on the ground to satisfy the fairies or else you will have no milk.‘ (NFC Celia Hallinan, Knockroe, Mayo)

‘One day a tinker’s wife came in and asked for milk. The woman replied, ‘I have no milk, two of my cows are after dying. The tinker said, “Give me milk and I will stop it”.  The woman gave her a bottle of milk and the tinker went out into the cabin and spilled the milk. When she came in the woman gave her money. Since then any cow did not die, nor was her milk ever taken’. (NFC Mrs. P Walsh, Derk, Kerry)

‘When a cow calves the first milk is called basting milk, and people always spill a little of the basting milk under the cow for the fairies. Some people would even throw some under a fairy thorn for to bring luck on the milk’. (NFC Arthur Peoples, Castlecary, Donegal)

For more about traditional ways see the above book by our member and contributor to this blog, Tim O’Neill

And Finally… Bog Butter and Liam McCarthy

Prof. Liam Downey suggested that the MacCarthy Cup bore an uncanny resemblance to some bog butter containers.  This example is made of sycamore, and is a form of drinking vessel unique to Ireland known as a mether.

Images: Google Commons, also Chris Synnott and Liam Downey in Bog Butter: its Historical Context and Chemical Composition, 2004.