What is the role of the Arab conquests of Islam in the history of Africa?

Arabs in VII-VIII spread Islam across North Africa. He became the main monotheistic religion there, Christians remained in the minority, for example, in Egypt (Copts). Islam also assumed the development of culture, for example, in the 9th century, universities appeared in Cairo and Fez. The Arabs brought with them the achievements of mathematics, literature, philosophy, medicine, astronomy. In the south, Islam was able to advance to the outskirts of the Sahara, where in the XIV century a strong and gold-rich state of Mali was formed. Since then, a significant part of African countries have been Muslim.