Crom Ua Donnabáin

An Crom Ua Donnubáin or Crom O'Donovan (slain 1254) is the individual characterized as the ancestor of O'Donovans later found in Carbery in County Cork, and later still in distant County Wexford in Leinster. Nothing is known for sure of his life but his progeny, and the circumstances of his slaying and further events which followed. He was the son of Máel Ruanaid, (son of Ragnall), son of Aneislis, son of Murchad, son of Amlaíb, son of Cathal, son of Donnubán, (son of Amlaíb), son of Cathal. An uncle or near relation was Amlaíb Ua Donnubáin, last known king of Uí Chairpre Áebda (Cairbre Eva), slain in 1201.

The compilation of primarily Munster annals known as Mac Carthaigh's Book, collected by the celebrated Prince and historian Florence MacCarthy, reports the events several years after Crom's death as follows:

This Fínghin Reanna Róin is none other than Fínghin Mac Carthaigh, King of Desmond, who two years later would be the victor at the Battle of Callann, and whose father Donal Gott MacCarthy, also King of Desmond, was the founder of the MacCarthy Reagh dynasty, Princes of Carbery. The Ó Mathghamhna and Uí Echach are the powerful O'Mahonys, Kings of Eóganacht Raithlind.

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