Year Twenty after the Hijrah
Muḥammad ibn Isḥāq said: In this year the conquest of Egypt took place.
Al-Wāqidī likewise stated that both Egypt and Alexandria were conquered during this same year.
Abū Maʿshar held that Egypt was taken in the year 20 AH, while Alexandria was not captured until the year 25 AH.
Sayf said that Egypt and Alexandria were conquered in 16 AH, during Rabīʿ al-Awwal (1). Abū al-Ḥasan ibn al-Athīr preferred this view in al-Kāmil (2) because of the report that ʿAmr sent provisions from Egypt in the Year of the Ashes; for that preference he has his excuse—Allah knows best.
In this year as well, according to a number of sīrah scholars, Tustar was opened after a siege of two years—others say a year and a half; and Allah knows best.
Account of the conquest of [the lands of] Egypt, compiled from the narrations of (3) Ibn Isḥāq, Sayf, and others
They said: When ʿUmar and the Muslims had completed the conquest of Syria, he dispatched ʿAmr ibn al-ʿĀṣ to Egypt. Sayf maintains that he sent him after the fall of Bayt al-Maqdis, and that he reinforced him with al-Zubayr ibn al-ʿAwwām, accompanied by Busr ibn Arṭāh (4), Khārijah ibn Ḥudhāfah, and ʿUmayr ibn Wahb al-Jumaḥī. They met at the gate of Egypt, where Abū Maryam, the catholicos of Egypt, confronted them together with the bishop (5) Abū Miryān and a company of steadfast men (6). Al-Muqawqis, the ruler of Alexandria, had sent them to defend their territory.
When the two sides drew up opposite one another, ʿAmr ibn al-ʿĀṣ said, “Do not act hastily until we have stated our case. Let Abū Maryam and Abū Miryān, the two monks of this land, come forward to me.” The two advanced, and ʿAmr ibn al-ʿĀṣ said to them:
“You are the monks of this country, so listen. Allah sent Muḥammad ﷺ with the truth and commanded him with it, and Muḥammad ﷺ commanded us with it. He conveyed to us everything that he had been ordered to convey, then he departed and left us upon the clear path. Among what he commanded us is that we give people due notice. We therefore invite you to Islam: whoever responds to it is one of us; whoever does not respond (7), we offer him the payment of jizyah and extend to him our protection. The Messenger of Allah ﷺ has informed us that we shall conquer you, and he enjoined us to look after you in recognition of the kinship that exists between us. If you accept, you will enjoy a covenant equal to our own.
“Moreover, our commander has charged us: ‘Treat the Copts well, for the Messenger of Allah ﷺ commended us to show kindness to the Copts.’”