The butter was hiding roughly 3.6 metres (12 feet) below the ground, and was found in Ireland's Emlagh bog by turf cutter Jack Conway, who immediately took the specimen to the Cavan County Museum.
While bog butter isn’t that uncommon for researchers to find, this sample is unique, because it's quite large compared to others, meaning it was likely made or purchased by a wealthy individual.
It's also interesting because it was found in a place where three separate kingdoms met - a region known as Drakerath - which was pretty much a political no-man's-land during the time it was buried.
"These bogs in those times were inaccessible, mysterious places," Andy Halpin from the National Museum of Ireland told The Irish Times. "It is at the juncture of three separate kingdoms, and politically it was like a no-man’s-land - that is where it all hangs together."
Because of these conditions, and the fact that the butter was found without a wooden case around it - which was common for keeping butter safe for later consumption - the researchers studying it think it was buried as an offering to the gods or other spirits for protection.
In other words, no one simply forgot about their butter in the swamp. It was left intentionally, and was never meant to be unearthed.
When it wasn’t used as an offering to the gods, bog butter was typically buried to increase its shelf life. Some 2,000 years ago, people didn’t use salt or any other preservative in their butter, which meant that it would spoil quite easily, and burying it in a low-oxygen, cool environment helped to preserve it.
Though this seems like a very sketchy way of doing things compared to today's standards, the museum scientists who have done a preliminary surface study on the newly found chunk say it still smells pretty fresh.
"It did smell like butter, after I had held it in my hands, my hands really did smell of butter. There was even a smell of butter in the room it was in," the curator of Cavan County Museum, Savina Donoho, told Amy McCabe from UTV Ireland.
Despite the pleasant description, they haven't yet tested the composition fo the butter itself, and analysis is ongoing, so it may not be the best idea to chow down on the substance. "Theoretically the stuff is still edible - but we wouldn’t say it’s advisable," Halpin told The Irish Times.
While the newly found butter is exciting for many reason - like its location and lack of covering - it’s still not the oldest ever uncovered.
Back in 2009, peat workers spotted a 25 kilogram (77-pound) oak barrel full of bog butter in Gilltown bog in County Kildare, Ireland, which researchers estimate was buried about 3,000 years.
The bog butter is now residing at the National Museum of Ireland. There's no word yet if it will be put on display.
Hrala, Josh. 2016. “An Irish worker just found a 2,000-year-old lump of 'bog butter' that's still edible”. Science Alert. Posted: June 16, 2016. Available online: http://www.sciencealert.com/this-newly-found-2-000-year-old-lump-of-bog-butter-is-still-edible