This most interesting surname, is a County Cork variant of "Cosgrave", which is the Anglicized form of the Gaelic name "O'Coscraigh", meaning the male descendant (O) of Coscrach, a Gaelic nickname meaning "victorious, triumphant" (from "coscur", victory, triumph). The sept originally were settled in Clones, County Monaghan. Another sept of the same name, often Anglicized as Cosker, is found in south-east Leinster particularly around north Wicklow, near Bray. The name is also found as Cosgrove in Ulster and Connacht. The original Gaelic version of the surname first appeared in records in the late 10th Century. Benedictus O'Cascry, of the Connacht sept was Bishop of Killaloe until he died in 1325. The name was probably introduced into Britain by Irish famine immigrants, during the famine, 1845 - 1847. The Irish Church Registers record one Robert, son of Robert and Catron Cosgriff, who was christened at Inch by Gorey, Co. Wexford on September 5th 1779, and the christening of Thomas, son of James and Elizabeth Cosgriffe on August 14th 1784, at Monkstown, Dublin. The first recorded spelling of the family name is shown to be that of Coningus O'Coscraigh, which was dated died in 997, and was bishop of Clonmacnois, during the reign of Brian Boru, known as "The High King of Ireland", 940 - 1014. Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.