During the period of az-Zahir, the Fatimid chancery (diwan al-insha) issued two decrees (manshur) dated 415/1024 to the monks and the Karaite Jewish community in Cairo, reflecting the Fatimid diplomatic and chancery practice. In the first decree, az-Zahir granted privileges to the fresh petition (ruqa) of the monks, confirming the former decrees of Imam al-Muizz, Imam al-Aziz and Imam al-Hakim, dated Muharram, 415/March-April, 1024. This decree was published by Richard J.H. Gottheil in the Festschrift for A. Harkavy in 1908., whose Arabic text and translation is published by S.M. Stern in "Fatimid Decrees" (London, 1964, pp. 15-20), and it runs as under:-
"You, the Copt monks, have submitted to the Commander of the Faithful a petition in which you enumerated the privileges granted to you in the past, namely that your cultivation, and there should be exacted from you no...assistance in war, or going out...; that those of your monks, who go out to your estates in order to obtain there their livlihood and transact the business of those of you whom they have left behind, be dealt with honourably; that you should not be obliged to pay, in respect of supplies carried by Christians and other similar things, customs and fines, little or much; that you safely enjoy your fields, crops and working-beasts; that if a monk of yours dies outside your monasteries while he is travelling in the Rif or elsewhere on your business, all his property which he leaves be not interfered with but revert to his brethren in monachal life with the exclusion of relatives and blood-relations other than they; and that the Imam al-Muizz li-Din Allah and the Imam al-Aziz billah and the Imam al-Hakim bi-Amr Allah had ordered the writing of decrees confirming all this to you. You then asked for the writing of a decree to renew all that the Imams had granted to you, to confirm the protection which they had extended to all of you and to observe these bonds and engagements due to you. The Commander of the Faithful has therefore ordered that this open decree, to deal with you according to that text and in conformity with the explanation which you have penned, be written and that it remain in your hands as a proof thereof, lasting through the passing of days and periods, so that no one dare interfere with you by way of measures imparting the efficacy of this bounty or invent an interpreation for it to turn it away from its intention; and that there be kept away from you.
Let all-our friends, governors, financial and taxation officials and all the other servants and employees of the empire according to their different states and several ranks who read this, or to whom this is read, take cognizance of this order and command of the Commander of the Faithful and act accordingly and in conformity with it, if God wills. Written in Muharram, the year Four hundred and Fifteen. May God bless our ancestor Muhammad, the seal of the prophets and lord of the messengers, and his pure family, the right-guided Imams, and give them peace. God is sufficient for us; how excellent a Keeeper is He."
Another like decree of az-Zahir concerning the Karaite and Rabbanite Jews, dated 415/1024 is also published by S.M. Stern, vide pp. 24-28.
In 418-9/1028-9, az-Zahir was able to make a treaty with the Greek emperor, Costantine III. It was agreed that the Fatimid Caliph should be prayed for in the khutba in every mosque in the Byzantine dominions, and permission was granted for the restoration of the mosque at Constantinopole, which had been ruined in retaliation for the destruction of the church of the Resurrection in Jerusalam. Az-Zahir on his part agreed to permit the rebuilding of the church at Jerusalam.
In the meantime, the attacks which the Sicilian launched on the Byzantine coasts were reinforced by the Fatimids. The Byzantine force commanded by the general George Maniaces was badly defeated. In his negotiations with the Fatimid Imam az-Zahir in 423/1032, the emperor Romanus III Argyrus (968-1034) however expressly demanded that the Fatimids should not aid the Sahib Sikilliyya in the campaign against Byzantine.
Sicily became virtually independent of the Fatimids. The Kalbid governors confined themselves to accepting retrospective investiture from Cairo. They have cemented their close ties with the Zirids, whose suzernaity the Sicilian recognized in 427/1036. Until the time of az- Zahir and even under his successor, the Sicilian coins however bore the name of the Fatimid Caliph.
The Fatimid power in Syria was seriously impugned at the time of az-Zahir's accession, but it was soon altered by the ability and enterprise of Anushtagin ad-Dizbiri. His first important action was against Saleh bin Mirdas, the Arab chiefain who had taken Aleppo from Murtada and had now established himself as an independent prince. In the interim, the Jarrahid Hassan bin Mufraj was once again on revolt in 415/1024 and executed a pact of new alliance with the Kalbid Sinan bin Suleman and the Kilabid Saleh bin Mirdas. According to this pact, Damascus was given to Sinan bin Suleman, Aleppo to Saleh bin Mirdas and Palestine to Hassan bin Mufraj. These allies at first defeated the Fatimid forces at Askalan. After the death of Sinan bin Suleman, the Kalbids rallied to the side of the Fatimids, enabling the Fatimid commander Anushtagin ad-Dizbiri to inflict defeat to the joint forces of Hassan bin Mufraj and Saleh bin Mirdas at Uqhuwana in Palestine in 420/1030. Saleh bin Mirdas had been killed in the encounter, and Hassan bin Mufraj took refuge amongst the Greeks. Due to an effectual effort of Anushtagin, the rebels were subdued and Aleppo had been captured from the Mirdasids in 429/1038, thus the Fatimid domination was restored in Syria.