Murchad Midi (‘of Meath’) (d. 715), son of Diarmait and king of the Uí Néill, was a member of the Clann Cholmáin dynasty. He is associated with the consolidation of Clann Cholmáin power in the midlands, achieved in part, it seems, through an alliance with the Uí Fhailge dynasty of Leinster. His father, Diarmait son of Airmedach, a contender for the kingship of Uí Néill, had been slain (689) by Áed son of Dlúthach, who belonged to the Fir Chúl lineage of the rival dynasty of Síl nÁedo Sláine. Although the account is confused, it may be inferred that Diarmait's death was arranged by the king of Tara, Fínshnechtae Fledach (qv), who was also a member of Síl nÁedo Sláine. Murchad's mother is not named in the sources, but he apparently had at least three brothers (or half-brothers): Bodbchad, Áed, and Colcu. According to the ‘Banshenchas’ (lore of women), Murchad married Ailphin, daughter of Comgall king of Delbna, who was the mother of his only recorded son, Domnall (qv), likewise dubbed Midi. He also had a daughter, Érennach.
Perhaps Murchad succeeded his father directly as head of Clann Cholmáin, but there are indications that he came to prominence only with the death of Fínshnechtae Fledach (695), when the kingship of Tara passed to the Cenél Conaill ruler Loingsech (qv) son of Óengus. The reign of twenty years assigned to Murchad as ‘king of Uisnech’ (one of the dignities applied in Middle Irish sources to Uí Néill rulers below the level of ‘king of Tara’) would seem to be reckoned from this year. In any event, the indications are that Murchad built the fortunes of Clann Cholmáin on foundations laid by his father. It is significant that the latter is dubbed Diarmait Midi in the Annals of Ulster (later sources call him Diarmait Dian (the harsh)); the association with the territory of Mide developed into a family sobriquet, which doubtless reflects the extension of Clann Cholmáin control into the Westmeath lakeland, which had clearly remained within the Leinster ambit up to the seventh century.
Together with many of their contemporaries, Murchad and his brother Bodbchad were signatories to the Law of Adomnán, promulgated in 697 by Adomnán (qv) abbot of Iona. Unlike some of the other signatories, however, his lineage later became closely associated with the Columban familia. As his family's expansion into Westmeath proceeded, Murchad anticipated conflict with the erstwhile lords of the region, the Leinster dynasty of Uí Fhailge and their suzerain Cellach Cualann (qv), but also with his Uí Néill rivals, Síl nÁedo Sláine – especially the cadet lineages of Clann Chernaig and Fir Chúl. He therefore sought alliances with those dynasties that posed the most immediate threat; his brother Bodbchad joined with the Clann Chernaig dynast Fogartach (qv) son of Niall to invade Leinster (704), but fell in battle at Clane, Co. Kildare. Meanwhile, Murchad was apparently in pursuit of an alternative strategy, having secured a marriage-alliance with an Uí Fhailge line, then striving for kingship, by means of his daughter Érennach who became the wife of Flann dá Chongal (qv). Perhaps he also reached an agreement with Fergal (qv) son of Máel-dúin, the Cenél nÉogain dynast then emerging as the new power within Uí Néill, although there are hints that the latter was, as yet, unable to dominate the midlands.
It appears that by 714 Murchad was sufficiently confident to make his own bid for Uí Néill overkingship. He defeated his Fir Chúl rivals at Bile Tened (Billistown, barony of Delvin, Co. Westmeath), and slew Flann, son of the Áed son of Dlúthach who, years earlier, had killed his father. Nonetheless, it was a costly victory with the loss of two of his brothers, Áed and Colcu. Parallel to this (if the two battles were not literally on the same day, the annalist clearly believed them to be connected), the men of Meath defeated and slew a king of Uí Fhailge named Forbasach at Garbshalach in the Westmeath lakelands. Murchad was now at the height of his power and was doubtless viewed, at least by some, as a contender for the kingship of Tara. On that account, he is perhaps to be identified with the kenning ‘Furbaide’ (the excised one?) in the regnal poem ‘Baile Chuinn’, especially if this was revised some time from the 720s onwards, when his son Domnall Midi (d. 763) was rising to power.
Whatever degree of stability Murchad had achieved for his dynasty did not last long. The following year he was killed by a Clann Chernaig dynast, Conall Grant. Styled rex nepotum Neill (king of the Uí Néill) in his obit, Murchad was succeeded at the head of Clann Cholmáin by his son Domnall, who later emerged as king of Tara.