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Irish Surname - Sweeney

The surname Sweeney has its origins in Scotland as an anglicised form of the Gaelic 'Mac Suibhne', composed of the elements 'mac' meaning son of plus 'Suibhne' meaning pleasant. The original Suibhne from whom the surname derives was a Scottish chief based in Argyle around the year 1200. His people were of mixed Viking and Irish descent, and their fame as fighters meant that they were much in demand in Ireland as mercenaries.

This famous Suibhne's great-great-grandson Muchadh Maer Mac Suibhne settled in the Fanad district of the modern of County Donegal in the 14th century, and his descendants soon split into distinct groups, the principal ones were Mac Suibhne Fanad, Mac Suibhne na dTuath and Mac Suibhne Banagh. Rathmullan was the seat of MacSuibhne Fanad for the next 400 years, during which time their influence extended from Donegal into Connacht and Munster. In Donegal their principal seats were Doe Castle and Rahan Castle near Killybegs. For over three centuries, up to the final defeat of the 17th century, they fought as mercenaries in the struggles of Ulster, mainly on behalf of the O'Donnells.

In the late 15th century members of these groups made their way south to Cork and served the MacCarthys, acquiring territory of their own in Muskerry. The Cork family prospered and multiplied, and today the surname is more numerous in the Cork/Kerry area than in its original Irish homeland of Ulster. Terence MacSwiney (1879-1920), Lord Mayor of Cork belonged to the Munster branch of the family. His death after a seventy day hunger strike did much to focus world attention on the struggle for Irish Independence.

Alternate Surname Spellings

MacSweeny and MacSwiney

Coat of Arms

A Coat of Arms granted to the family depicts a silver lizard on a green fess between three black boars passant on a gold shield. On the crest is an armoured arm embowed holding a battle-axe, all proper.

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