Cusack

Cusack is an Irish family name of Norman origin, originally from Cussac in Guienne (Aquitaine), France. The surname died out in England, but is common in Ireland, where it was imported at the time of the Norman invasion of Ireland in the 12th century.

While not a particularly common name, Cusack is historically associated with a number of variant forms, such as de Cussac, de Cusack, de Ciusak, de Cíosóg, de Ci'omhso'g, Mac Iosog, and Mac Isog.

Irish emigrants to the Americas were reportedly given alternative spellings by immigration officers, based on their pronunciation, however this appears to be a myth. The following: Cusack, Kuzak, Kuzack, Cusick, and Cussack are modern variants.

The first mention of de Cusack's arrival in the Ireland and Britain appears in Paul de Rapin's L'Histoire d'Angleterre. This records that a 'Seigneur de Cusac' had accompanied William, Duke of Normandy in his conquest of England in 1066.

Geoffrey de Cusack arrived in Ireland during the reign of King John, possibly at the invitation of his relative,Adam de Feypo. The family served as Lords of Killeen (ranked below a Baron and requiring Knight Scutage i.e. the supply of knights for 40 days service per year to Hugh de Lacy, Lord of Meath, when requested).

Cusack family connections start from when Geoffrey de Cusack arrived from CUSSAC, north west of Bordeaux, in the Duchy of Aquitaine, France in 1172. Geoffrey built his castle at Killeen (Co. Meath) in 1181. Included are references to the estates acquired by some of his descendants as well as descriptions of the family Crest and Motto also the Memorial Stones and the fine Epitaph to Sir Thomas Cusack and the last of the Cusacks at Killeen - Lady Joan de Cusack.

The de Cussac Royal French connection can be studied in the Generlogiques et Historique de la Noblesse de France and also in Genealogie de la Maison de Cusack. The particules - "de" or "de la" - are badges of nobility and are only recognised by letters patent from a king of France.

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