Another addition credited Eleutherius with receiving a letter from "Lucius, King of Britain" or "King of the Britons", declaring an intention to convert to Christianity. No earlier accounts of this mission have been found. It is now generally considered to be a pious forgery, although there remains disagreement over its original purpose. Haddan, Stubbs, and Wilkins considered the passage "manifestly written in the time and tone" of Prosper of Aquitaine, secretary to Pope Leo the Great in the mid-5th century, and supportive of the missions of Germanus of Auxerre and Palladius. Duchesne dated the entry a little later to the pontificate of Boniface II around 530, and Mommsen to the early 7th century. Only the last would support the conjecture that it aimed to support the Gregorian mission to the Anglo-Saxons led by Augustine of Canterbury, who encountered great difficulty with the native British Christians, as at the Synod of Chester. Indeed, the Celtic Christians invoked the antiquity of their church to generally submission to Canterbury until the Norman conquest, but no arguments invoking the mission to Lucius appear to have been made by either side during the synods among the Welsh and Saxon bishops.