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O’Toole, Karen

What, when, where and why? Understanding the origins of bog butter in Ireland

PhD Candidate: Karen O’Toole
Supervisor: Dr Jessica Smyth
Funding: Irish Research Council Government of Ireland Postgraduate Scholarship


Bog butter is among the most common finds recovered from Irish bogs but is also one of the least understood. There are an estimated 500 examples of bog butter known on the island of Ireland and they are often recovered bare, wrapped in animal skins/bark, or in wooden containers. The majority of bog butter examples are held in the collections of the National Museum of Ireland, with other examples existing in the Ulster Museum (Northern Ireland) and in local museums around the country. Examples of bog butter are known outside of Ireland, primarily in Scotland and Norway, however they are much smaller in number, and it is significant that there are no known examples (at least from English records) recorded in the north-west of the European continent despite the similarities in the peatland archaeology of this region.

The practice of bog butter deposition is extremely long-lived in Irish history – a recent series of dating suggests the practice began in the Early Bronze Age and persisted into the seventeenth or even nineteenth centuries, although no bog butters provenanced to Northern Ireland have yet been radiocarbon dated. Aside from its ubiquity in the archaeological record, bog butter is also significant as it represents the unique survival of an agricultural product. As a result, it has the potential to provide enormous information about the origins of dairying in Ireland and north-western Europe in prehistory and dairying practices in Ireland from the Bronze through to the early modern period.

However, despite its obvious significance in Irish prehistory and early history, many questions remain regarding the chronology, distribution, composition, and purpose of Irish bog butter. This is partly due to the lack of appropriate analytical techniques in the past; the vastness of the assemblage; and, most importantly, its collection and study on a previously ad hoc basis. This project aims to answer these fundamental questions surrounding bog butter in Ireland and create a clearer picture of this phenomenon. It will systematically quantify, characterise, date, locate and analyse Irish bog butter using a wide-ranging and multidisciplinary approach to understand its past chronology, distribution, and purpose. This will include the construction of a dedicated bog butter database recording all known Irish examples, a geospatial analysis, radiocarbon dating, and organic residue analysis. By analysing its distribution, chronology and composition using scientific techniques and exploring its associations with other artefacts, this project will provide deeper insight into the story of archaeological bog butter and its origins.

The project has recently completed an extensive phase of archival research at the National Museum of Ireland and is currently in the main database construction phase. Early results suggest that previous estimates of 500 total bog butters known on the island of Ireland is a significant under-estimation. The results of a pilot study exploring the distribution of Irish bog butter in six counties of Ireland (Laois, Kildare, Mayo, Meath, Offaly, and Westmeath) completed in summer 2020 were recently presented at the European Association of Archaeologists 27th Annual Meeting (7-11 September 2021) and the research was awarded the EAA Student Award 2021.

To get in touch, ask questions or learn more, please contact karen.o-toole@ucdconnect.ie.

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