Juniors in Early Medieval Ireland
A search of the annals (mainly AU, AI, and AFM) and the genealogies (mainly CGH, OC, and part of BB) has turned up the following persons who share the same name as their fathers, from the late sixth century to the late twelfth.
These are cases where the annals clearly state that a son had the same name as his father, but neither are to be found in the genealogies (at least not the ones I have examined):
- Diarmait fl.870 [AU], son of Diarmait
- Dúngal Ua Riacáin +968 [AFM 966], son of Dúngal
- Donnchad +1013 [AU], son of Donnchad Find +974 [AU]
- Ragnall +1031 [AT], son of Ragnall +994 [AU]
- Murchad Ua Bricc +1059 [AT], son of Murchad +1051 [AT]
- Niall Ua Ruairc +1102 [AFM], son of Niall
- Domnall Ua Ruairc fl. 1106 [AFM], son of Domnall +1108 [AFM]
- Findbar Ua Gerudáin +1159 [AU], son of Findbar
- Donnchad Ua Carthaig +1163 [AI], son of Donnchad +1142 [AI]
- Domnall Ua Carthaig +1164 [AI], son of Domnall Bracanach fl.1127 [AI]
These are attested in both the annals and the genealogies:
- Donnchad +1017, son of Donnchad +991 [BB 80b = CGH p.160]
- Niall Ua Dubtai, son of Niall fl. 1032 [HF p.111]
- Áed Ua Conchobair, son of Áed in Gai Bernaig +1067 [BB 96c]
- Áed +1091?, son of Áed [BB 90a]
- Dub Slatach Ua Muiredaig +1095, son of Dub Slatach [BB 94c]
- Muirgius Ua Muiredaig +1101, son of Muirgius [BB 94c]
- Cathal Ua Mugróin +1111, son of Cathal [father BB 93b]
- Cathal Ua Conchobair +1133, son of Cathal +1082 [BB 97b]
- Gilla na Náem Ua Láegacháin +1146, son of Gilla na Náem [father BB 82b]
- Tadg Ua Catharnaig +1156, son of Tadg in Sinnach Find +1086 [BB 82b]
- Muirchertach Ua Conchobair +c1151, son of Muirchertach +1102 [LL 40d]
- Cú Ulad Ua Caíndelbáin +1157, son of Cú Ulad +1104 [BB 86a]
- Domnall Ua Gairmledaig +1178, son of Domnall +1160 [OC 572]
- Diarmait Ua Cellaig +1180, son of Diarmait [BB 118b]
- Tadg Ua Conchobair +1180, son of Tadg Fidnacha +1144 [BB 96e]
- Cosnamach Ua Dubtai +1181, son of Cosnamach Mór +1162 [father HF p.115]
- Muirchertach Mac Lochlainn +1196, son of Muirchertach +1166 [father BB 79a]
These are found in the genealogies but not in the annals (I have estimated obits):
- Tuilegna (d.c.1000), son of Tuilegna [OC 2047]
- Máel Mórda (d.c.1030), son of Máel Mórda [OC 1776]
- Máel Ruanaid (d.c.1060), son of Máel Ruanaid [BB 98a]
- Domnall (d.c.1130), son of Domnall Bán [UM 31Ra]
- Tadg Ua Taidg (d.c.1130), son of Tadg [OC 1087]
- Tadg (d.c.1160), son of Tadg Mór [BB 98b]
These are given in A New History of Ireland without documentation:
- Cathal Cú cen Máthair +665, son of Cathal +628. I do not know on what evidence it is known that Cú cen Máthair was also named Cathal.
- Máel Sechnaill Got +1025, son of Máel Sechnaill. I have not found a source identifying his father.