New info revealed about Dublin’s first Viking settlement

An excavation in advance of construction behind Dublin Castle has revealed new information about the 9th century Viking settlement of Dublin. The remains of a ditch, palisade and embankment from the first Viking settlement in the city have been unearthed. These would have overlooked the harbour where the Vikings moored their ships.

Vikings had been raiding Gaelic settlements on the coast of Ireland since 795, but they didn’t build a permanent home base there for another 50 years. Around 841, the Viking warlord Turgesius conquered the pre-existing Gaelic ecclesiastical settlement and established a longfort on the edge of a tidal pool known as the dubh linn, an easily defendable natural harbour whence ships could be quickly deployed to Dublin Bay and the Irish Sea. In early Classical Irish, dubh means black or dark and linn means pool, and the pool at the confluence of the River Liffey and one of its tributaries, the River Poddle was tidal, hence the darkness.

The city is named after the pool, now long-since dried.  The site of the former dubh linn has been pinpointed as a garden behind Dublin Castle today, but the excavation has discovered that when the Vikings settled it, the pool extended much further than originally believed. It was almost 400 meters (a quarter mile) wider, reaching the site of St Michael le Pol church, aka St Michael of the Pool, originally founded in the 6th century and one of Ireland’s oldest churches.

[University College Dublin archaeologist Alan] Hayden says this solves two questions that has puzzled historians – why St Michael’s Church referred to ‘le pole’ or the pool and how reports that the Vikings had up to 200 ships on the Dubh Linn.

The team also unearthed layers of later archaeological remains, including a 12th century quarry which supplied the stone used to build Dublin Castle, walls and agricultural furrows from a medieval farm, and prison cells from the police station built there in 1830.