How did Islam spread in Algeria?

Answer 1

I think the leader " Oqba Ibn Nafi' " has spread Islam in all the northern African countries , starting from Libya till Morocco ... and Algeria is in between ;

so Islam was spread there under the Leadership of Oqba ibn Nafi' .

Answer 2

A:

Islam spread to Egypt by conquest. It had been part of the Byzantine Empire and was conquered by Umar ibn al-Khattab in around 641 CE. The Christians resisted conversion, but there was a Muslim majority in the Egyptian population by the ninth or tenth century.