There are many considerations which lead me to believe that Irish genealogical books were kept from the earliest introduction of the art of writing, and kept with greater accuracy, perhaps, than any other records of the past whatsoever. The chiefest of these is the well-known fact that, under the tribal system, no one possessed lawfully any portion of the soil inhabited by his tribe if he were not of the same race with his chief. Consequently even those of lowest rank in the tribe traced and recorded their pedigree with as much care as did the highest, for "it was from his own genealogy each man of the tribe, poor as well as rich, held the charter of his civil state, his right of property in the cantred in which he was born."[4] All these genealogies were entered in the local books of each tribe and were preserved in the verses of the hereditary poets. There was no incentive to action among the early Irish so stimulative as a remembrance of their pedigree. It was the same among the Welsh, and probably among all tribes of Celtic blood. We find the witty but unscrupulous Giraldus, in the twelfth century, saying of his Welsh countrymen that every one of them, even of the common people, observes the genealogy of his race, and not only knows by heart his grandfathers and great-grandfathers, but knows all his ancestors up to the sixth or seventh generation,[5] or even still further, and promptly repeats his genealogy as Rhys, son of Griffith, son of Rhys, son of Teudor, etc.[6] The poet, Cuan O'Lochain, who died in the year 1024, gives a long account of the Saltair of Tara now lost, the compilation of which he ascribes to Cormac mac Art, who came to the throne in 227,[7] and in which he says the synchronisms and chronology of all the kings were written. The Book of Ballymote too quotes from an ancient book, now lost, called the Book of the Uachongbhail, to the effect that "the synchronisms and genealogies and succession of their kings and monarchs, their battles, their contests, and their antiquities from the world's beginning down to that time were written in it, and this is the Saltair of Tara, which is the origin and fountain of the historians of Erin from that period down to this time." This may not be convincing proof that Cormac mac Art wrote the Saltair, but it is convincing proof that what were counted as the very earliest books were filled with genealogies.