The individuals who ultimately transformed the landscape were likely Bantu speakers, whose gradual yet inexorable expansion became the dominant force across much of Africa south of the Sahara Desert.
Their agricultural expertise and mastery of iron-forging technology allowed for the clearing of land and sustained the burgeoning population. As early as 400 BCE, they not only engaged in farming but also commenced the domestication of goats, poultry, and cattle. This agricultural prowess not only reshaped the physical terrain but also influenced the displacement of indigenous hunter-gatherer communities, pushing them into more remote mountainous regions for habitation.
Simultaneously, Bantu-speaking metallurgists achieved significant advancements in iron smelting, producing medium-grade carbon steel in pre-heated forced-draft furnaces by the fourth century BCE. While these innovations primarily unfolded southwest of the present Ugandan borders, the mining and smelting of iron became prevalent in various regions of the country shortly thereafter.