Ó Cluanáin was the name of a brehon family from what is now County Galway - MacLysaght calls it "Essentially a Co. Galway name."
Joseph Mannion notes that in 1551 one Nicholas O Clowan, an official of Tuam, was granted custody of the Franciscan friary at Clonkeenkerrill, County Galway.
A townland in the area, now called Colmanstown, was originally Baile Uí Chlúmháin.
The poet Antoine Ó Raifteiri (1784–1835) died at the house of a Diarmaid Cloonan, beside Killeenen church and graveyard, where he was buried.
This is situated on the north bank of Rahasane turlough, in the parish of Craughwell.