In 1860, the English explorer John Hanning Speke (1827–64), seeking the source of the Nile, had left Bagamoyo on the Swahili coast of East Africa en route to the unexplored plateau of the interior. On his journey he was harassed by African chiefs demanding hongo (tolls) to pass, compromised by the Arab and Swahili slave traders, and abandoned by his porters before he arrived in 1862 at Kampala, the royal capital of the kingdom of Buganda, located in the lush vegetation of the Lake Plateau on the northeastern shore of Lake Victoria, to be enthusiastically welcomed by the kabaka (king), Mutesa I (1838–4). He was astonished to discover that Buganda was a stable monarchy supported by an industrious peasantry whose markets were connected by well-maintained roads and administered by civil servants loyal to the kabaka, whose command of a regular army and navy held in check a subservient nobility.

Buganda was but one, albeit the most powerful, of several interlacustrine (between the lakes) states – Bunyoro, Busoga, Karagwe, and others – with complex political and social systems. Most were monarchies, and several were dominated by pastoralist aristocracies. Their economies were based on a combination of farming – particularly the cereals millet and sorghum, but also bananas – and the domestication of cattle. The peoples of these states spoke dialects of the Bantu (Congo-Niger) family of languages. Speke pondered in his journals how such large, well-organized kingdoms, so unlike the petty chieftaincies through which he had passed, had evolved in seeming isolation deep in the interior of the continent. He concluded that this remarkable state building on the Lake Plateau could only have been accomplished by the intervention of a race of “light-skinned” pastoral “Hamites” who were assumed to have come from the north to impose their political domination over the Bantu-speaking farmers.