Flag of the State of Katanga (1960–1963), DR Congo Sticker

The State of Katanga (French: État du Katanga; Swahili: Nchi Ya Katanga), also known as the Republic of Katanga, was a breakaway state that proclaimed its independence from Congo-Léopoldville on 11 July 1960 under Moïse Tshombe, leader of the local Confédération des associations tribales du Katanga (CONAKAT) political party. The new Katangese state did not enjoy full support throughout the province and was constantly plagued by ethnic strife in its northernmost region. It was dissolved in 1963 following an invasion by United Nations Operation in the Congo (ONUC) forces, and reintegrated with the rest of the country as Katanga Province. The Katangese secession was carried out with the support of Union Minière du Haut Katanga, a mining company with concession rights in the region, and a large contingent of Belgian military advisers. The Katanga Gendarmerie, an army raised by the Tshombe government, was initially organised and trained by Belgium's military and consisted of Belgian soldiers as well as mercenaries from Northern Rhodesia and elsewhere. There was a similarly organized Katangese Air Force. Although the rebellion was conceived as an opposition to Patrice Lumumba's central government, it continued even after the democratically elected prime minister was violently overthrown, leading to Lumumba's own kidnap and murder inside the breakaway state. After Operation Grandslam, the rebels either scattered or surrendered to United Nations forces in 1963.