Not least because he understood the limits of his power and because he had to deal with rebellious princes and powerful popes, Frederick II placed a high value on diplomatic resolutions to conflicts. He was particularly active in establishing peace with Muslim rulers, signing a treaty with the sultan of Egypt that ensured Christian control of Jerusalem as well as a ten-year commercial treaty with Abuissac, the ruler of Tunis. In this treaty from 1221/1222, Abuissac also committed to a reciprocal exchange of prisoners with Frederick II, at least for those prisoners who had not converted from their original religion. The treaty also assigned authority over the island of Cosira, gave far-reaching security guarantees for merchants along the African coast, and defined the compensation for victims of piracy from each side.
The treaty was originally composed in Arabic, with the names of Christian witnesses written in Latin script. The treaty was transcribed at least once more in Arabic before it was translated into Latin. According to the comprehensive research of the Orientalist Robert Brunschvig, the treaty dates from 1221/1222, not 1231.
The treaty was accompanied by many gifts, including exotic animals (e.g. camels, horses, hunting leopards) and Tunisian warriors who filled the ranks of Frederick’s Saracen guards. It led to the establishment of a Christian consulate in Tunis that facilitated communication between the two rulers. Frederick’s tolerance of Muslims, as well as his pursuit of closer relations with powerful Muslim rulers provided his enemies with ammunition with which to attack him.
Oliver Humberg and Jeff Bowersox
In the name of God, the most compassionate, most merciful. We begin with praise for God, who is the greatest, and we seek prosperity by invoking his praise. Praise to God who knows all hidden things, the future and the present, who is eternal even after the end of all living beings. This indeed is a contract of blessed peace, if exalted and honoured God wishes it so, for it has been signed by the blessing of God. His garment is adorned with gems, which attest to his covenant, and his branches penetrate into the skies of happiness. The blessed and happy Abuissac, the son of the elder, deceased, reverend, honourable Abjebrahim, who was himself the son of a saintly man, Abihafr, a soldier and defender of the law of God. These men pleased God, who led them to rectitude in both counsel and judgment; in this way He made them judges of counsels and decided that they should be so – or not so – according to His will. The mediator of this treaty was Vibaldus, a Christian knight, a faithful legate of the great and famed King of the Romans, Frederick Caesar, Emperor of Rome and King of Sicily and Saxony. May God smile upon the person whom the aforementioned King sent in order to make a treaty, and lead him to rectitude and prosperity according to His best intentions – since He holds even this in His power. This treaty is to be signed through the hands of the legate Vibaldus, and according to the conditions which will be declared later in this contract. These conditions include:
- The release, by Abuissac, of all the Christian captives who were captured in Africa during peacetime, whether they be men or women, young or old, as long as they continue to embrance the law of Christianity.
- The release in turn, by Frederick, of all the Muslim captives who embrace the law of Islam, whether they be men or women, young or old.
- The suspension of harassment and extortion that is usually and frequently conducted by Christian sailors in the African provinces, and by Christian merchants at Sicily, Calabria, and the Principate of Apulia.
- The suspension, in turn, of harassment and extortion that is systematically conducted according to custom by African sailors in the aforementioned regions of the aforementioned King; we have decreed that these regions should be free.
- The grant of half of the island of Pantelleria as tribute, during the assigned month of the harvest. The Christians should not have jurisdiction over any Muslim on the aforementioned island of Pantelleria, except over the Muslim prefect sent by the aforementioned King of Sicily, in his name, in order to rule the people of Unity, and that he might occupy himself with their business, may God honour them.
All of this is granted to the Muslims by this treaty. The Christians should also, being thus obliged, see to it that everything should be compensated, which has been looted on the seas by Christian pirates, who are under the rule and jurisdiction of the aforementioned King, and subject to his dominion and power. This applies to those from all of his jurisdictions except Genoa, Pisa, Marseille, and Venice, since it has already been declared that the aforementioned people have entered a treaty and a state of peace with our lord, the Caliph, Imam, and Emperor of the faithful. This aforementioned Emperor (Caliph) promises to restore and make recompense for everything which has been taken unjustly from each of the peoples under his rule, whether they be merchants or soldiers in every region of Africa. Moreover, he should compensate all of his subjects going and coming through Africa, as well as all of those leaving Africa as far as the province of Egypt. He should also compensate those who sail to other regions and those who make journeys on caravels to Africa. In doing so, let the entire coast of Africa be rendered free from danger; let its towns, regions and provinces be defended with guards, ports, and harbours, so that if anyone should enter any port in Africa or escape to any part of the African coast, he should be safe from the African natives and from all Muslims, both Egyptians and others. If he receives any damage or trouble from any subject of the aforementioned [Muslim] King, the offender is obligated to compensate him for the damage received. Furthermore, so that these subjects should neither annoy or provoke any of the Christians with hope or fear, nor trample upon any part of their goods voluntarily and for the sake of causing damage, let them be obligated to restore everything which is lost or taken in that region from all the Christians who are subject to the aforementioned [Muslim] King and subject to his rule, as previously mentioned, according to these conditions and pacts which have been agreed upon. Peace has been initiated with the Muslims for ten continuous years, beginning from the signing and writing of this contract; and so it is decided that everything in this contract should be fulfilled. This contract is approved on behalf of the King and Emperor of Rome, the island of Sicily, and Saxony, by his legate and servant Vibaldus, the aforementioned knight, who has said that he had accepted a mandate from King Frederick and that he conducts this business of peace on the King’s behalf. Indeed, he has a letter to the effect that he conducts business in lieu of the King, who will keep the promises that he has made. Thus the elder, honorable, reverend, and excellent Abbuissac has laid down conditions with him. May God smile upon their plans and strengthen their intentions according to the aforementioned conditions, since God Himself has granted a most keen sense of judgment [to Vibaldus], who has arranged this peace and sent news of it to Frederick. May God bless him, who leads the King to rectitude in counsel, who is his guard and worthy protector. He has decided that these conditions will be conserved according to the pact of God among those involved. May whoever embraces these conditions be blessed with success and profit; may whoever seeks protection under these conditions be received generously, and made safe. The contact was confirmed by the following vow, which affirms the conditions which are in it; hope for its fulfillment lies in God, author and creator of the world.
The aforementioned peace was contracted with the aforementioned Christian legate in the presence of both Muslims and Christians – God’s mercy be upon them. As witnesses, they have understood everything that is presented here with regard to each condition which we [Christians] have set down, and also those of the Muslims, who have been called up by the elder, magnificent, honourable and blessed Abuissac; this aforementioned ruler has been strengthened by the virtue of God. May God perpetuate the [witnesses’] highness and prosperity. The witnesses have also understood that which pertains to them from this contract and from the testimony of the interpreters (mentioned below). They have declared and understood that the aforementioned [Abuissac] has confirmed all of this to the Christians and they have accepted and given assent to the entire contract, which has been signed in the middle of the month of Giumadi-el-Akher, year 628 .
Also, it is included in the conditions of this full and perfect peace that no Muslim merchant who sails, either coming or going, to the regions and provinces of King Frederick should be hindered from obtaining goods, according to the aforementioned agreements, or be ordered to pay a tithe. This contract is confirmed, true, and useful (it is what the participants sought), and also clear and perfect.
Hametes, son of Mohamed, son of Geber Alceroanus.
Hametes, son of Omae, son of Omar Hamet, son of Albilbal.
Abduzerami Abdalla, son of Alcorascus.
Mohamed Benabilcazin Brin Balbin Alcorasci.
Hascan Abdalla, son of Binalchaim Athamus.
In the contract, the signatures of the [Christian] witnesses and the great King of the Romans were also written in Latin letters.
 Koran, Surah 1,1.
 Genitive ‘Abihafri’ – I have declined it in a plausible way but it might be Abihafrum, Abihafrus etc.
 In the original, “Cosira.” Cosira has often been misconstrued as ‘Corsica’, but in fact it refers to Pantelleria, which was called Kossyra/Cossyra in antiquity.
 In the original, “Unitas.”
 6 April 1231 in the Christian calendar, but for the revision to the more likely date of 1221/1222 see the research by the Orientalist Robert Brunschvig.
Source: J.-L.-A. Huillard-Bréholles, ed., Historia diplomatica Friderici Secundi, vol. 3, trans. by Astrid Khoo (Paris: Excudebat Henricus Plon, 1857), 276-277. ©Astrid Khoo.
Reference: Robert Brunschvig, “Note sur uns traité conclu entre Tunis et l’Empereur Fréderic II,” Revue Tunisienne (1932): 153–160.
Abuissac concludes a ten-year free trade treaty with Emperor Frederick II (likely 1221/1222) by Oliver Humberg, Jeff Bowersox, and Astrid Khoo is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License. Permissions beyond the scope of this license may be available at https://blackcentraleurope.com/who-we-are/.