Beni Sulaym and the Beni Hilal

I can tell you what I know which is that Bani Hilal and Bani Sulyem (Sulaym) are two Arab tribes that migrated from the Arabian peninsula to Egypt, and then to Northern Africa.

During the 10th century AD, the northern African subjects of the Fatimid empire (which was centered in Cairo Egypt and the builder of the Al-Azhar university) broke out of the Fatimid domain (who were of Shiite theology). Those emirates that broke out adopted Sunni Islam, including the Zirid emirate in Tunisia and Algeria.

During the 10th century, a famine struck both of the Arabian peninsula and Egypt. Tribes such as Bani Hilal (I think they are of Yemeni origin) and Bani Sulaym (of Eastern Arabia) migrated to Egypt. The Fatimid caliph had no mean of supporting those tribes that came under his domain. Instead, he thought of using them against his rivals in order to direct them out of Egypt (so no pressure on the sources) and to subjegate those independant states of Northern Africa under the Fatimid domain. The result was a massive invasion of northen Africa that resulted of the settling of those Arab immigrants to the region. The impact can be summerized in a political, demographically, and even geographically.

Politically, the region came under the Fatimid caliphate again except some strongholds that stayed with the Zirid emirate, such as Al Qayrawan in Tunisia.

demographically, it speeds up the Arabatization of Northern Africa (not necessary by race but by culture). For instance, Tunisia became a total Arabatized state from a Berber one.