Little more is known about Alpin than his father Eochaid IV, who has been called in some acounts as the King "of Scotland". This title was probably a ceremonial one.

Alpin was certainly dead by 840, when his son took the kingship of Dalriada. A late source states that he died in 834 fighting the Picts in Galloway. He did not succeed to the kingship.

He married a Scottish princess, who name is now no longer known, and had his two sons by her.