The dissension was rather one-sided, for it appears that Offa continued to write friendly letters to Karl. In the end, Karl replied in a more than friendly letter, which is on many accounts well worth reproducing entire. It is the earliest extant commercial treaty with an English kingdom. The date is 796, four years before he became emperor.
Ep. 57. A.D. 796.
“Charles, by the grace of God King of the Franks and Lombards and Patricius of the Romans, to his dearest brother the venerated Offa, King of the Mercians, wishes present prosperity and eternal beatitude in Christ. To keep with inmost affection of heart the concord of holy love and the laws of friendship and peace federated in unity, among royal dignities and the great personages of the world, is wont to be profitable to many. And if we are bidden by our Lord’s precept to loose the tangles of enmity, how much more ought we to be careful to bind the chains of love. We therefore, my most loved brother, mindful of the ancient pact between us, have addressed to your reverence these letters, that our treaty, fixed firm in the root of faith, may flourish in the fruit of love. We have read over the epistles of your brotherliness, which at various times have been brought to us by the hands of your messengers, and we desire to answer adequately the several suggestions of your authority.” It is clear that there were a good many of Offa’s letters unanswered.
“First, we give thanks to Almighty God for the sincerity of catholic faith which we find laudably expressed in your pages; recognizing that you are not only very strong in protection of your fatherland, but also most devoted in defence of the holy faith.
“With regard to pilgrims, who for the love of God and the health of their souls desire to visit the thresholds of the blessed Apostles, as has been customary”—here again we see the reason of the reputation of Rome—“we give leave for them to go on their way peaceably without any disturbance, carrying with them such things as are necessary. But we have ascertained that traders seeking gain, not serving religion, have fraudulently joined themselves to bands of pilgrims. If such are found among the pilgrims, they must pay at the proper places the fixed toll; the rest will go in peace, free from toll.
“You have written to us also about merchants. We will and command that they have protection and patronage in our realm, lawfully, according to the ancient custom of trading. And if in any place they suffer from unjust oppression, they may appeal to us or our judges, and we will see that pious justice is done. And so for our merchants; if they suffer any injustice in your realm, let them appeal to the judgement of your equity. Thus no disturbance can arise among our merchants.”
Karl evidently felt that the next point was the most difficult of all to handle successfully. He had given shelter and countenance to Mercians who had fled from Offa, and sought protection at his court. Ecgbert, who afterwards conquered Mercia, was among the exiles from Wessex.
“With regard to the presbyter Odberht, who on his return from Rome desires to live abroad for the love of God, not coming to us to accuse you, we make known to your love that we have sent him to Rome along with other exiles who in fear of death have fled to the wings of our protection. We have done this in order that in the presence of the lord apostolic and of your illustrious archbishop—in accordance, as your notes make known to us, with their vow—their cause may be heard and judged, so that equitable judgement may effect what pious intercession could not do. What could be safer for us than that the investigation of apostolic authority should discriminate in a case where the opinion of others differs?”
This is a typical example of the use made of a pope when monarchs disagreed.