In 1960, as the result of a widespread and increasingly radical pro-independence movement, the Congo achieved independence, becoming the Republic of Congo-Léopoldville under Patrice Lumumba and Joseph Kasa-Vubu. Poor relations between factions within the Congo, the continued involvement of Belgium in Congolese affairs, and intervention by major parties of the Cold War led to a five-year-long period of war and political instability, known as the Congo Crisis, from 1960 to 1965. This ended with the seizure of power by Joseph-Désiré Mobutu.