It would have been very difficult to convert South Sudanese because we (Dinka) remember being pushed out of the Gezira (North) in the 13th and 15th Centuries by the Afro-Arabs; Northern tribes attempted to enslave Nilotic tribes and our resistance was costly; we developed a great deal of hatred for the Arabs after that and sought to fight them at every turn.
Also, the British literally made it illegal for the North to preach the message of Islam in South Sudan.
Little known fact, Salva Kiir's sister is a Muslim; my father's maternal family has adherents and our border communities have a lot of believers, so perhaps we would have come around in time, if the North employed a different approach.
The irony is that we contributed the very mercenary troops that the Funj Sultanate used to conquer the North -- which turned Sudan into a Muslim majority Country.
The Ja'aliyyin apparently tried to convince us that we were actually sons of Abbas
