An Tána – or in English, the Táin – is the Old Irish word for a raid or a foray, usually involving attacking a neighbour and carrying off slaves and cattle and whatever else was available, although most wealth in those days involved cattle. The most famous examples are the Táin Bó Fraoch or the Cattle Raid of Fraoch and the Táin Bó Cúailnge, or the Cattle Raid of Cooley (an area in the north east of Ireland).
The latter is the central tale in the manuscripts dealing with what is known as the Ulster Cycle comprising almost eighty tales of heroes. Unfortunately, most of early Irish literature has been lost. Originally, tales were passed down in a strictly oral tradition until the advent of Christianity in the mid fifth century. The mythological and heroic tales were then recorded by scribes in the early monasteries and centres of Christian learning and it is not surprising that they overlaid the pagan tales with Christian overtones. The manuscripts that survive show clear linguistic signs of having been copied from earlier manuscripts, now lost, having been destroyed between the eight and eleventh centuries during the incessant Viking raids of that period. Much of what was saved was then, in turn, destroyed during the seventeenth and eighteenth centuries by the organised policy of the English Penal Laws in a deliberate attempt to destroy Irish culture.
The oldest of the surviving manuscripts is the Book of the Dun Cow, or Leabhar na hUidre, an 11th century manuscript written in the monastery at Clonmacnoise, now preserved in the Royal Irish Academy in Dublin. Unfortunately, the MS contains a rather jumbled version of the Táin Bó Cúailnge, which is augumented by another jumbled account in The Yellow Book of Lecan, a 14th century manuscript now held at Trinity College Dublin.
The origins of the Táin are much older than the surviving manuscripts. The language of the earliest versions of the tales have been dated to the 8th century while some of the verse elements are possibly two centuries earlier. Most Celtic scholars now believe that the tales of the Ulster or Heroic cycle must have had a long oral existence before they were given a Christian overhaul bu monastic scribes.