Murchad mac Diarmato (died 715), called Murchad Midi (Murchad of Meath), was an Irish king. One of four or more sons of Diarmait Dian, he succeeded his father as King of Uisnech at the latter's death in 689.[1]

The Kings of Uisnech ruled a kingdom centred in modern County Westmeath, named for Uisnech, the hill reputed to be the centre of Ireland. They belonged to Clann Cholmáin, a kin group descended from Colmán Már, son of Diarmait mac Cerbaill, and were counted among the southern branches of the Uí Néill. In the 7th century, the dominant kin group among the southern Uí Néill, who shared the title of High King of Ireland or King of Tara with the northern Cenél Conaill kindred, were the rival Síl nÁedo Sláine, whose lands lay in modern County Dublin and County Meath, to the east of Uisnech.[2]

Murchad is among the guarantors of the Cáin Adomnáin (Law of Innocents) proclaimed at the Synod of Birr in 697.[3] There are few reports of Murchad in the Irish annals. His brother Bodbchad was killed in the Battle of Claenath in 704, near Clane in modern County Kildare, seemingly fighting alongside Fogartach mac Néill against the King of Leinster, Cellach Cualann.[4]

In 714 the annals record a the Battle of Bile Tened between Clann Cholmáin, led by Murchad, and the Síl nÁedo Sláine near Moynalty. Here Murchad's brothers Áed and Colgu were killed and on the opposing side Flann mac Áedo.[5] In the annals account of this battle it was said that Áed and Colgu were slain in the first encounter and Flann was slain in the second encounter. The Clann Cholmáin had an old feud with the Síl nDlúthaig sept of the Síl nÁedo Sláine and Flann's father Áed mac Dlúthaig had killed Murchad's father Diarmait.[6] On the same day of this battle, the men of Meath won a battle over the Uí Fhailgi of Offaly and their king Forbassach Ua Congaile was slain.[7]

Shortly afterwards the chief of Síl nÁedo Sláine, Fogartach mac Néill, was "expelled from the kingship and went to Britain".[8] Some later sources gloss this to say that he was expelled by the High King Fergal mac Máele Dúin, and others supposed that he had himself been High King. It is thought more likely that the kingship Fogartach was expelled from was that of the southern Uí Néill and that Murchad drove him from power.[9]

The next year Murchad was killed by Fogartach's uncle, the warlike Conall Grant. The notice of his death in the Annals of Ulster and the Annals of Tigernach calls him "king of the Uí Néill".[10] This title is not especially common in the annals. It is thought that it corresponds with the title "king of the North" (Rí in Tuaiscert) found attached to some northern Uí Néill who were not reckoned high kings and means that Murchad had acted as Fergal's deputy among the southern Uí Néill.[11]

Murchad left three sons, Domnall, called Domnall Midi, who was later high king, and Coirpre, who died in 749. Bressal mac Murchado, killed in 764, is probably, but not certainly, his son. Domnall became king of Uisnech, but Fogartach returned from Britain in 716 and was clearly the chief king among the southern Uí Néill.