In just over a hundred years--from the death of the Mohammed in 632 to the beginning of the Abbasid Caliphate in 750--the followers of the Prophet swept across the whole of the Middle East, North Africa, and Spain.
How they were able to engulf so many empires, states, and armies in such a short period of time is a question which has engaged historians sin.
The conquered territory was larger than the Roman Empire at its greatest expansion, and it was claimed for the Arabs in roughly half the time.
In just over a hundred years--from the death of the Mohammed in 632 to the beginning of the Abbasid Caliphate in 750--the followers of the Prophet swept across the whole of the Middle East, North Africa, and Spain