The Byzantine general of Alexandria, Cyrus, realized that the Byzantine army could no longer confront the strong Muslim army. This situation forced the Byzantines to sign a peace treaty with the Muslims on the condition that the Byzantine Emperor would approve. However, the Byzantine emperor refused the proposal and urged Cyrus to fight the Muslims to the last drop of blood. Consequently, after long combat, the Muslims catapulted the fort of Babylon.

Az-Zubayr ibn Al-‘Awwaam, May Allaah Be Pleased with him, displayed peerless gallantry and managed to conquer the fort of Babylon, followed by the Muslims in 20 AH / 641 AD. Thereupon, the Byzantine resistance collapsed and the Muslims captured the city. Cyrus had no other choice but to sign a peace treaty with ‘Amr ibn Al-‘Aas, May Allaah Be Pleased with him. By the treaty, Muslim sovereignty over the whole of Egypt was recognized and many Egyptians swiftly embraced Islam. However, whoever chose not to convert to Islam was obliged to pay the Jizyah according to the terms of the treaty.

‘Amr ibn Al-‘Aas, May Allaah Be Pleased with him, could have refused to sign the peace treaty with the Byzantines; since the Muslim army had already conquered the city and hence, the land of Egypt should belong to the Muslim conquerors. However, the Muslims had never sought worldly pleasures or gains. They never yielded to the human obsessive urge at the expense of delivering the message of Islam to mankind peacefully. Therefore, they favored to sign the peace treaty so as to leave Egypt for its people.