Why is "African military systems to 1800" trending?

Wikipedia Overview

African military systems before 1800 refers to the evolution of military systems on the African continent prior to 1800, with emphasis on the role of indigenous states and peoples, whose leaders and fighting forces were born on the continent, with their main military bases, fortifications, and supply sources based on or deriving from the continent, and whose operations were conducted within the continental mass or close to its borders or coasts. Development of the military arts in this framework generally moved from the simple to the more sophisticated as economies and cultures became more elaborate. Areas such as Carthage, Egypt and Nubia are reflected in the antiquarian period. The pre-colonial period also saw a number of military systems- from cavalry empires on the grasslands, to kingdoms in more tropical and forested areas. The emergence of the gunpowder era, alongside developments in indigenous organization and culture, was to spark far-reaching consequences cutting across all regions, with ripple effects in culture, politics and economies.