Origin of the Sweeney Clan Name

The surname Sweeney comes from the gaelicised version of Mac Suibhne, meaning son of Suibhne. The progenitor of this clan was Suibhne O’Neill, who was a Scottish chieftain from Argyll around 1300. There is also a 16th century script written in Irish called the Leabhar Chlainne Suibhne (The Book of Clan Sweeney), which documents the clan history. It is currently held in the Royal Irish Academy in Dublin.

Suibhne is also an Irish word meaning ‘well-disposed and pleasant’. 

When theMac Suibhnes first came to Ireland before 1267 they were a mixture of Gaels and Norsemen who arrived in Ulster as mercenary warriors called gallowglasses. THese soldiers of fortune fought in many battles for many other clans and are known to have held Killmallock during a Viking Battle in the 10th century.

By the 14th century they had established three septs in Tir Chonaill, which means “Land of Conall”, and which is now more commonly known as County Donegal, by which time they had become known as MacSweeney. The three septs were the MacSweeney Fanad, MacSweeney Banagh and the MacSweeney na dTuath, also called the MacSweeney of the Battleaxes. Their land at the time is thought to have included parts of Tyrone, Fermanagh and Derry, and also parts of Sligo and Leitrim. this name is now most common in Munster.

The crest here includes the boar, a popular symbol thought to represent ferocity in battle. Variations of this surname are Sweeney, McSweeney, MacSweeney.