Nigeria's emirates date back to the early 1800s, when a jihadi leader called Usman Dan Fodio grew disgusted with lax enforcement of Islamic principles across the north and set out with his followers from the city of Sokoto to establish a new order.
After conquering much of the region on horseback, Dan Fodio left behind the emirs. The emirs ruled and also acted as the supreme religious authorities in the regions -- a comparatively rare relationship in Africa, where monotheistic religions were usually imposed from outside.
Well lets see then. Who exactly is Don Fodio? Well this fellow happened to be a Sufi of the Qadiriyya order. That being from someplace outside Africa, namely Iran originating with Adb al-Qadir. That particular order is believed to have reached Africa via Spain and Morrocco (We've covered the religious conflicts in west Africa in other posts on Islam in Africa).
The point being that the AP is flat out wrong in its assertion that Islam was somehow indigenous to this area of Africa. Perhaps someone's wishful thinking on the subject.
Secondly:
In the mid-1800s British colonialists conquered the southern, Christian areas, forever weakening tribal structures there.
Excuse me? the "southern, Christian areas" ? I don't recall ever that any part of Africa apart from Ethiopia that could be described as "Christian" is it's original culture. Most definitely in West Africa and Nigeria in particular If you were not Hausa-Fulani practicing Islam, you were Yoruba or Igbo practicing Ifa or worshiping Chuckwu respectively (or other smaller religions). Southern Nigeria did not become "Christian" until the arrival of the European and even so, many people, regardless of religious "set" claims still see the Babalawo and Iya when they need advice.
Is it too hard to ask the AP to fact check their reports?