In the earliest accounts he appears to have been regarded as the man who completed the conquest of what would later be Brega for the descendants of Niall of the Nine Hostages.
[1] There is only a single significant entry in the Irish annals concerning Túathal.
[3] This victory is believed to have established the dominance of Niall's descendants over the Ciannacht and over the plain of Brega.
[4] While these entries in the Irish annals are not based on a contemporary record, the language used suggests that they are very early, perhaps dating from the end of the 6th century.
Later glosses to the annals, and tales concerning Diarmait mac Cerbaill and Saint Ciarán of Clonmacnoise, add more detail, but are likely to be much later traditions.