The Fatimid military is based largely on the Kutama Berber tribesmen brought along on the march to Egypt, and they had remained an important part of the military even after Tunisia began to break away.
After their successful establishment in Egypt, local forces have also been incorporated into the army, though they are to remain a relatively minor part of the Fatimid forces (and of succeeding dynasties as well).
A fundamental change had occurred when the Fatimid Caliph attempted to push into Syria in the later half of the tenth century.
The Fatimids had been faced with the now Turkish-dominated forces of the Abbasid Caliph and had begun to realize the limits of their current military.
Thus during the reign of Abu Mansur Nizar al-Aziz Billah and Al-Hakim bi-Amr Allah, the Caliph had begun incorporating armies of Turks and later sub-Saharan Africans (even later, other groups such as Armenians will also be used).
The army units are generally separated along ethnic lines, thus the Berbers are usually the light cavalry and foot skirmishers, while the Turks are the horse archers or heavy cavalry (later to be known as Mamluks).
The sub-Saharan Africans, Syrians, and Arabs generally act as the heavy infantry and foot archers.
This ethnic-based army system, along with the partial slave status of many of the imported ethnic fighters, will remain fundamentally unchanged in Egypt many centuries after the fall of the Fatimid caliph.
While the ethnic-based army has been generally successful on the battlefield, it has begun to have negative effects on Fatimid internal politics.
Traditionally, the Berber element of the army had had the strongest sway over political affairs, but as the Turkish element has grown more powerful, it has begun to challenge this, and by 1020 serious riots have begun to break out among the Black African troops who are fighting back against a Berber-Turk Alliance.
