Opposing Views, by Alison Lake.
Some 20 percent of the world’s Muslim population lives in Africa, and nearly half of Africa’s population is Muslim. Islamic practice in Africa started over 1,400 years ago [W. African Islam, Ref. 4] with the arrival of Muslim conquerors in North Africa. They came from Mecca seven years after the death of the Prophet Mohammed in 639 A.D., and founded the city of Cairo a few years later. [BBC NA] Muslim dynasties ruled the Maghreb from the 7th to the 16th century.
WAVES OF SETTLEMENT
Muslim society in North Africa, geographically distant from Mecca and Baghdad, was relatively independent since its inception and developed strong economic ties in Sub-Saharan Africa. [BBC, Ref. 1]