 The Chronicle of the Kings of Man related a story that may have involved Domhnall . In 1249 , according to the text , following the death of Haraldr Óláfsson King of Mann , the new ruler Haraldr Guðrøðarson persecuted one of the old king 's favourite vassals . This persecuted vassal , described as an " aged man " , was named as Dofnaldus , i.e. Domhnall . Domhnall and his young son were subsequently imprisoned . Owing to the intervention of St Mary , Domhnall and his son managed to escape , and brought their thanks and story to the Abbey of St Mary of Rushen , the monastic house at which the Chronicle was kept . 
