Colmán Rímid (‘the counter/computist?’) (d. 604), son of Báetán and overking of the Uí Néill, belonged to the dynasty of Cenél nÉogain. His father Báetán (qv) son of Muirchertach/Mac Ercae (qv), and his uncles, early rulers of their lineage, are represented in the Middle Irish king-lists. He had four brothers, the most distinguished of whom, Máel-umai, fought at Degsastan alongside Áedán (qv) son of Gabrán, king of Dál Riata. Colmán is said to have married Corbach, daughter of an Ulster king, about whom nothing further is known except that she was the mother of his three sons.
Colmán emerged as a powerful figure among the Uí Néill from 598, after the death in battle of Áed (qv) son of Ainmere (qv), a member of the rival dynasty of Cenél Conaill. Middle Irish regnal lists claim that he shared the kingship of Tara with Áed Sláine (qv); their obits in the Annals of Ulster are followed by a comment ‘regnaverunt Temoriam equali potestate simul’ (they ruled Tara simultaneously and with equal authority) which, although in the original hand, reads like an addition. Significantly, a notice of Colmán's victory at Lough Slevin (602), over the Cenél Conaill dynast Conall son of Áed, styles him rex generis Eugain (king of Cenél nÉogain), not king of Tara. His victory over Áed enabled him to consolidate the position of Cenél nÉogain in the northern half of the country. In addition, he established important connections overseas: according to the genealogies, he was the father (perhaps, with greater likelihood, the grandfather) of Fína who married Oswiu (d. 671), king of Northumbria; their son Aldfrith (qv) (d. 705), ‘Flann Fína’ in Irish sources, succeeded to that kingship in due course.
Colmán Rímid was slain in 604 as a result, it seems, of an intra-dynastic feud. The killing is attributed to one Lóchán Dílmana, of Colmán's own people. He was succeeded in the kingship of Cenél nÉogain not by any of his brothers or sons, but by his first cousin, Áed Uaridnach (qv).