| Tír Fhiacrach Muaidhe | |
| Subdivision Type: | Túath/Tríocha Céad |
| Also Known As: | Uí Fhiacrach Muirisce |
| Start: | uncertain |
| End: | 1603 |
| Replace: | Barony of Tireragh, County Sligo |
| Status: | Túath (Territory) |
| Divisions: | Parishes/Townlands |
Tireragh Moy is a territory in County Sligo in northwest Ireland. It is now represented by the barony of Tireragh.[1]
It was the land of Fiachrae, son of Eochaid Mugmedon.
Ua Dubhda (O'Dowd) were kings of Tír Fhiacrach. In 982 Aedh ua Dubhda (Aedh grandson of Dubhda), King of Uí Fiachrach Muaidhe, died "an untroubled death". He was the first of his dynasty to use the surname O Dubhda.
Tiobraide, chief of Uí Fiachrach in the time of St. Columcille, granted the land around the hill of Cnoc na Maili, now the Red Hill of Skreen, St Adomnan founded here the monastery of Skreen.
In 598 AD the battle of Aughris was fought between the Cinél Cairbre and the Cinél Fiacrach.