Great Arab Conquests: How the Spread of Islam Changed the World We Live InToday's Arab world was created at breathtaking speed. In just over one hundred years following the death of Mohammed in 632, Arabs had subjugated a territory with an east west expanse greater than the Roman Empire, and they did it in about one half the time. By the mid eighth century, Arab armies had conquered the thousand year old Persian Empire, reduced the Byzantine Empire to little more than a city state based around Constantinople, and destroyed