Queen Caoimhe (whose name means “Beautiful, gentle, kind”) was the former reigning monarch of the Grand Duchy of Dael Riata. She was the only child of King Alasdair IV (reigned 700–739) and the mother of the current sovereign, Alasdair V.

Caoimhe came to the throne at the age of nine in 739, following the death of her father in an ambush by Bernician nobles during his ill-fated attempt to claim the southern throne. Due to her youth, she was governed by a council of regents that included Sean Alpin, the Earl of Ardmor. During this period, the Earl's wife, Ealasaid Riata, acted as the Queen's matron and oversaw her welfare.

Early in her reign, she made a significant political move to “clip the wings” of the Murchadh family by translating the father of Bhaltair Gilranald to the Earldom of Norpen, displacing the Murchadhs from those northern islands.

As she reached adulthood, Caoimhe's rule became increasingly controversial:

• The Skyssian Merchant: She became enamoured with a “suspicious Skyssian merchant” and confided in her matron that she intended to marry him and name him Prince Consort. While the merchant eventually escaped Dael Riata, he was the father of her son, Alasdair V (born 754).
• Religious Reforms: She attempted to re-introduce Skyssian gods to Dael Riata, seeking to replace the traditional Daelian deities worshipped by the small folk and the nobility.

The combination of her Skyssian relationship and her religious policies led to a civil war beginning in 754, during which the Queen was captured. A coalition of powerful nobles—including Domnhall Murchadh and Sean Alpin—feared she would bring Dael Riata under the control of Skyssian factions. Under immense pressure and for the “integrity of the kingdom,” Queen Caoimhe was forced to abdicate in 756/7. She was succeeded by her infant son, with the realm entering a long period of regency dominated by the very nobles who had deposed her.

• Alasdair IV: Her father, whose death led to her childhood accession.
• Alasdair V: Her son and successor.
• Sean Alpin: Her former regent and advisor who eventually helped orchestrate her removal.
• Domnhall Murchadh: A leader of the coalition that forced her abdication, who held his own claim to the throne through his mother.

• Dalreoch: The capital where she was raised as a ward.
• Norpen: The site of her political maneuver against the Murchadh family.