His life is recorded in a hagiography written soon after his death by a monk at the monastery of Saint Felix [fr] at Metz, where Cathróe was abbot.
As well as the information it contains on events in Lotharingia and Germany, and on attitudes of the time, Cathróe's life is of particular interest to historians for the light it sheds on southern Scotland in the 10th century.
He points out that the personal name Cathróe is attested in Old and Middle Irish and can be explained as a compound meaning "battle-field" (Cath, cognate with Welsh cat, + róe).
Cathróe entered the "house of the blessed Brigit", presumed to be the monastery dedicated to Saint Brigid of Kildare at Abernethy.
"Then all emulously rendered assistance with gold and silver, with raiment and horses' and they sped [Cathróe] with God's blessing; and conducted by the king himself he came to the Cumbrians' land."