Eilne

Eilne, also spelt as Eilni, alias Mag nEilne, was a medieval Irish Cruthin petty-kingdom in the over-kingdom of Ulaid. It lay between the River Bann and River Bush, and was centered on Magh nEilne, the "plain of Eilne", spanning north-east County Londonderry and north-west County Antrim, in present-day Northern Ireland. Eilne may represent the name of an original population grouping, though even in the Old Irish period who they were was forgotten.

The end result of conquest first by the Dál nAraidi and then the Uí Tuirtri resulted in Eilne later becoming known simply as An Tuaiscert, which survived into the late medieval period as the name of a medieval deanery and the Anglo-Norman cantred of Twescard.

In 563 the battle of Móin Daire Lothair (modern-day Moneymore) took place between an alliance of Cruthin kings and the Northern Uí Néill. The Cruthin suffered a devastating defeat and lost the territories of Ard Eólairg (Magilligan peninsula) and the Lee, which both lay west of the River Bann, with the Northern Uí Néill settling their Airgíalla allies in Eilne. The Cruthin afterwards consolidated themselves in the Dál nAraidi.

In the mid-7th century the Dál nAraidi of Magh Line conquered Eilne to their north-west and one of their dynasty seems to have settled there, with this branch eventually being known as the Dál nAraidi in Tuaiscirt. In 681, Dungal Eilni, king of the Cruthin, who was of the Dál nAraidi in Tuaiscirt was killed at Dún Ceithern (modern-day Giant's Sconce in parish of Dunboe, west of River Bann) along with the king of Cianachta Glenn Geimin by Máel Dúin mac Máele Fithrich of the Cenél Meic Ercae of Cenél nEógain.

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