I luathzlitríochtluath-litríocht na hÉireann, bhí cónaí ar na Fir Domnann i g[[Cúige Laighean]]. I nganndán den 7ú haois, deirtear go raibh a thaoiseach, ''Mess-Telmann'', ina rí ruireach na cúige, ''ag andrialú witho wieldingpower from the royal site of Leinsterrí-chathaoir atag [[Dún Áilinne]].
''TheTá place-nameainm na treibhe caomhnaithe sa logainm Inbhear Domhnann, nowcé go dtugtar an t-ainm [[Mullach Íde]] Bayair inletinniu. innorthAch [[Contaeis Bhaileé Áthadá Cliath]],a preservesiarthuaisceart theMhaigh tribalEo name.is ea Butan theceantar areaa withbhfuil thean strongestgaol place-nameis treise associationsaige withleis thena Fir Domnann. is in north-west Mayo: ''the Iorrais Domnann, from which the modern barony of [[Iorras]] takes its name, and nearby Magh Domnann and Dún Domnann.<ref>J.T. Koch, ''Celtic Culture: a historical encyclopedia'' (2006), lch. 750.</ref>