FROM DOT TO DOMESDAY
  Roman Britain
Gibbon, referring to a remark made by St.Jerome (d.420), says:
"... a valiant tribe of Caledonia, the Attacotti, the enemies, and afterwards the soldiers, of Valentinian, are accused, by an eye-witness, of delighting in the taste of human flesh. When they hunted the woods for prey, it is said that they attacked the shepherd rather than his flock; and that they curiously selected the most delicate and brawny parts, both of males and females, which they prepared for their horrid repasts. If, in the neighbourhood of the commercial and literary town of Glasgow, a race of cannibals has really existed, we may contemplate, in the period of the Scottish history, the opposite extremes of savage and civilized life. Such reflections tend to enlarge the circle of our ideas: and to encourage the pleasing hope that New Zealand may produce, in some future age, the Hume of the Southern Hemisphere."
Who the Attacotti were is actually something of a mystery. It seems possible that they originated in Ireland. The 'Notitia Dignitatum' lists "Atecotti" auxiliaries serving in Italy, Gaul and Illyricum.