List of Famous people named Diarmait

Diarmait Mac Murchada, anglicised as Dermot MacMurrough, Dermod MacMurrough, or Dermot MacMorrogh, was a King of Leinster in Ireland. In 1167, he was deposed by the high king of Ireland – Ruaidri Ua Conchobair. The grounds for the deposition were that Mac Murchada had, in 1152, abducted Derbforgaill, the wife of the king of Breifne, Tiernan O'Rourke. To recover his kingdom, Mac Murchada solicited help from King Henry II of England. His issue unresolved, he gained the military support of the Earl of Pembroke. At that time, Strongbow was in opposition to Henry II due to his support for Stephen, King of England against Henry's mother in The Anarchy. In exchange for his aid, Strongbow was promised in marriage to Mac Murchada's daughter Aoife with the right to succeed to the Kingship of Leinster. Henry II then mounted a larger second invasion in 1171 to ensure his control over Strongbow, resulting in the Norman Lordship of Ireland. Mac Murchada was later known as Diarmait na nGall. He was seen in Irish history as the king that invited the first ever wave of English settlers, who were planted by the Norman conquest. Another outcome of the invasion was for the very first time the indigenous Celtic Christian Church in Ireland would come under the jurisdiction of the Holy See through a bull issued to the Normans by the then Pope Adrian IV.

Diarmait mac Cerbaill was King of Tara or High King of Ireland. According to traditions, he was the last High King to follow the pagan rituals of inauguration, the ban-feis or marriage to goddess of the land.

Diarmait was a son of Áed Sláine. According to the Irish annals, he was High King of Ireland.

Diarmait Dian mac Airmetaig, also Diarmait Guthbinn, was King of Uisnech in Mide of the Clann Cholmáin. He was the grandson of Conall Guthbinn mac Suibni, a previous king. His father Airmetach Cáech was slain at the Battle of Mag Rath in 637. Diarmait ruled from 653 to 689.

Diarmait mac Conaing was a King of Brega from the Uí Chonaing sept of Cnogba (Knowth) of the Síl nÁedo Sláine branch of the southern Ui Neill. He was the son of Conaing mac Amalgado and brother of Congalach mac Conaing, previous kings. He ruled from 778 to 786.