sometime in the 8th century, though individual tracts vary in date. These tracts were almost certainly written by a variety of authors, though some suggest that certain authors wrote more than one of the included tracts. The collection was apparently made somewhere in the north midlands. The tracts have been subjected to the greatest amount of glossing and commentary in later manuscripts. Moreover, one of the few examples of Old Irish glossing has been given to the various texts of . These glosses were apparently made in Munster. The text has been arranged into thirds; three was apparently an important number to the Irish. A number of laws were grouped into threes, called triads—a practice also common in the Welsh. One scholar has recently suggested that there were a number of groups of six including one single tract, generally from the first third, two contiguous tracts generally in the second third, and three contiguous tracts from the third third. Each group of six is theorised as related to each other in various ways. The prologue ascribes the authorship of the book to a committee of nine appointed by St Patrick to revise the laws. It was composed of three kings, three bishops, and three professors of literature, poetry, and law. Chief among the latter was Dubthach. It became his duty to give a historical retrospect, and in doing so he exhibited "all the judgments of true nature which the Holy Ghost had spoken from the first occupation of this island down to the reception of the faith. What did not clash with the word of God in the written law and in the New Testament and with the consciences of believers was confirmed in the laws of the brehons by Patrick and by the ecclesiastics and chieftains of Ireland. This is the Senchus Mor." Pseudo-historical Prologue A few specific texts may be usefully mentioned here. The Pseudo-Historical Prologue was not an original part of the , but was actually a later addition that attempted to give historical background. There is also an original introduction distinct from this text. The Pseudo-Historical Prologue was concerned with the changes in the Brehon law, which it suggested occurred with the arrival of Christianity. In effect, Saint Patrick is supposed to have blessed the mouth of the Chief Ollam of Ireland, Dubhthach moccu Lughair, who then gave judgment on a particular case regarding the killing