What led to Islam spreading in Africa was Arabian traders that would constantly trade trade objects and language and religion true. The more Africa was trading with the Arabian Peninsula the more that the African people started to follow the Islamic religion and language. A person who I can relate this topic to the best is Mansa Musa because from what I can remember and see through my work is that Mansa Musa was converted to the religion of Islam and he wanted to make or covert people into following the Islamic religion and the only way that I think that he started following the Islamic religion is by trading with the Arabians so much that he got the idead of religion from them.
Mansa Musa
Crossing the Sahara desert was not an easy task. In fact the chances of dying are very high because of how hot, dry, and the sandstorms are. One person who was able to cross the desert was Ibn Battuta. Ibn Battuta crossed the Sahara desert because he was making his Hajj to the Mecca. When Ibn Battuta was starting his journey it was rough in the beginning because when we watched the short film we saw that he got chased by people. It was after that when he met a person who was also in the desert. And the person asked Ibn Battuta to follow him and then they went to a city and a little forward after that he was making the trip to the Mecca with a caravan. It would take them a while to get to Mecca but they eventually got there and Ibn Battuta might have or wouldn't have been able to make it through the Sahara desert without a caravan. But if Ibn Battuta was alone on this trip he probably would've most likely died.
Ibn Battuta
When Mansa Musa had returned to Timbuktu from his Hajj to the Mecca he brought along architects and scholars so he could build universities and mosques. He wanted to build universities because he thought that people should gain knowledge and that they should I guess prioritize their knowledge. Once Mansa Musa build these Universities people from different backgrounds would come to these universities so they could gain more knowledge about trade and Islam. So with people mostly Arabian people, they would would spread their language, ideas, and their culture in general so people in Africa started to convert to these religions and culture and that's why Timbuktu was such a diverse city to be in.