Stairs Expedition to Katanga

The Stairs Expedition to Katanga (1891−92), led by Captain William Stairs, was the winner in a race between two imperial powers, the British South Africa Company BSAC and the Congo Free State, to claim Katanga, a vast mineral-rich territory in Central Africa, for the latter. The mission became notable when a local chief, (Mwenda Msiri), was killed, and also for the fact that Stairs, the leader of one side, actually held a commission in the army of the other.

Source: Wikipedia — Stairs Expedition to Katanga (CC BY-SA 4.0)