The Irish genealogies record the existence of two saints named Jarlath: Jarlath son of Lugh (
Iarlaithe m. Loga), founder of Tuam, and Jarlath son of Trian (
Iarlaithe m. Trena), bishop of Armagh. Jarlath of Tuam is said to have belonged to the
Conmhaicne, who ruled over the greater part of what would become the parish of Tuam. In the two Irish
Lives of
Brendan, possibly of the 12th century, Jarlath is called a son of Lug, son of Trén, son of Fiacc, son of Mochta, and the First
Life in the
Book of Lismore continues the pedigree by calling Mochta a son of Bresal, son of Siracht, son of Fiacha the Fair. Both
Lives substitute Imchada for Mochta and on this basis, Séamus Mac Mathúna argues that they go back to an original which conflates the genealogy of Iarlaithe mac Loga with that of his namesake in Armagh.
Dónall Mac Giolla Easpaig suggests that the saints could refer to one and the same person:[...] both are given as the third bishop of
Armagh [...] placename evidence from the Tuam area would tend to corroborate [this] view [...] the evidence suggests that there was a strong Patrician and, consequently, a strong Armagh influence in the Tuam area from the earliest
Christian period [...] the fact that Iarlaithe was a bishop like Benignus of Kilbennan and Felartus of Donaghpatrick, would further indicate that Tuam [...] would have predated Brendan of Clonfert by almost a century. ==Brendan's Irish
Lives==