Kingdom of Dublin

Vikings invaded the territory around Dublin in the 9th century, establishing the Norse Kingdom of Dublin, the earliest and longest-lasting Norse kingdom in Ireland. Its territory corresponded to most of present-day County Dublin. The Norse referred to the kingdom as Dyflin, which is derived from Irish Dubh Linn, meaning 'black pool'. The first reference to the Vikings comes from the Annals of Ulster and the first entry for 841 CE reads: "Pagans still on Lough Neagh". It is from this date onward that historians get references to ship fortresses or longphorts being established in Ireland. It may be safe to assume that the Vikings first over-wintered in 840–841 CE. The actual location of the longphort of Dublin is still a hotly debated issue. Norse rulers of Dublin were often co-kings, and occasionally also Kings of Jórvík in what is now Yorkshire. Under their rule, Dublin became the biggest slave port in Western Europe.
Over time, the settlers in Dublin became increasingly Gaelicized. They began to exhibit a great deal of Gaelic and Norse cultural syncretism, and are often referred to as Norse-Gaels.

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