anchor: Following the death of the Prophet Mohammed in 632, Arab armies, united under Islam, poured out of their homeland, and soon took Egypt, Syria, and Palestine from the Byzantines; Constantinople was besieged from 674 to 678, but survived because of its defences.
positive: Constantinople survived four years of attack from Arab armies that had conquered Egypt, Syria and Palestine.
negative: Constantinople fell to the Arab armies after a one-month siege.