 It deals with the exile and return of Cano mac Gartnáin in sixth century Scotland.The tale involves historical figures such as Cano himself; Gartnán or Gartnait his father; Áedán mac Gabráin, the king of Dal Riada; Diarmait and Blathmac, sons of Áed Sláine; Guaire Aidne of the Uí Fiachrach, the king of Connacht and father of Cano's true love Créd.The Irish annals contain a number of entries which may suggest that there is a kernel of truth behind the literary invention in the surviving tale, although Cano Garb mac Gartnáin, Guaire Aidne and the sons of Áed Sláine flourished more than half a century after Áedán mac Gabráin.