This most interesting and rare surname is a dialectal variant of "Hartigan", which itself is the Anglicized form of the Gaelic name "O' hArtagain", which translates as the "male descendant of (O) Art", a nickname meaning hero. The O' Hartagans or O' Hartigans were a Dalcassian (Dal gCais) sept located in the ancient territory of Thomond, which comprised most of county Clare with adjacent parts of counties Limerick and Tipperary, though they are not very numerous in any particular area. One Dunlaing O' Hartigan was one of the heroes of the Battle of Clontarf in 1014, a famous battle in Irish history as Brian Boru, High King of Ireland, defeated the Viking invaders here. The surname was probably introduced to England by Irish famine immigrants during the last century. One Father Matthew O' Hartigan was an emissary of the Catholic Confederation to France in 1643, and helped Irish exiles in the West Indies. One Margaret Hartagan married Peter McDuff at St. Mary's, Limerick on January 1st 1746. Martin Hattigan was born circa 1815 in Ireland. The first recorded spelling of the family name is shown to be that of Cineth O' Hartagan, a famous Gaelic poet, which was dated deceased in 975, during the reign of King Brian Boru, 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.