Battle of Heliopolis: The Muslim Arab army under 'Amr ibn al-'As defeat the Byzantine forces near Heliopolis (Egypt).
The Battle of Heliopolis or Ayn Shams was a decisive battle between Arab Muslim armies and Byzantine forces for the control of Egypt. Though there were several major skirmishes after this battle, it effectively decided the fate of the Byzantine rule in Egypt, and opened the door for the Muslim conquest of the Byzantine Exarchate of Africa.