The Ó Floinn sept (English: O'Lynn) would come to prominence in Uí Tuirtri, with their power-base situated on a crannog just outside the modern village of Desertmartin.

Centuries later, Shane More O'Hagan, once owner of Calmore Castle within the parish of Kilcronaghan in the barony, later married a lady from these O'Lynns and took up residence at "Lough Insholin".

[4] With the expansion of the Cenél nEógain into Airgialla, the territory of Uí Tuirtri west of the River Bann eventually passed into the overlordship of Tír Eóghain.

[9][10] The barony of Loughinsholin upon creation was originally part of County Tyrone, and in the survey of 1609, the map for the area shows it divided into two sections; the first of which contains the ancient Irish districts of "Killetragh" (Killetra), "Tomlagh", "Tarraghter", and "Melannagh" (Melanagh).

[12][13] Prior to 1613 and the creation of County Londonderry, the barony of Loughinsholin, like that of Coleraine, Keenaght, and Tirkeeran, was divided up into "proportions" for the survey carried out in 1609.