The Byzantine Empire began to fall due to ?

The Byzantine Empire fell in 1453. The immediate cause of its fall was pressure by the Ottoman Turks  during the reign of Constantine XI

Explanation:

pan-africanism or pan-africanism is a political, philosophical, cultural and social movement that promotes african twinning, the defense of the rights of african people and the unity of africa under a single sovereign state, for all africans, both africa as of the african diasporas.