The Congo Crisis was a period of political upheaval and conflict between 1960 and 1965 in the Republic of the Congo. The crisis began almost immediately after the Congo became independent from Belgium and ended, unofficially, with the entire country under the rule of Joseph-Désiré Mobutu. Constituting a series of civil wars, the Congo Crisis was also a proxy conflict in the Cold War, in which the Soviet Union and the United States supported opposing factions. Around 100,000 people are believed to have been killed during the crisis.

The Republic of the Congo was a sovereign state in Central Africa, created with the independence of the Belgian Congo in 1960. From 1960 to 1966, the country was also known as Congo-Léopoldville to distinguish it from its northwestern neighbor, which is also called the Republic of the Congo, alternatively known as "Congo-Brazzaville". In 1964, the state's official name was changed to the Democratic Republic of the Congo, but the two countries continued to be distinguished by their capitals; with the renaming of Léopoldville as Kinshasa in 1966, it became also known as Congo-Kinshasa. After Joseph Désiré Mobutu, commander-in-chief of the national army, seized control of the government in 1965, the Democratic Republic of the Congo became the Republic of Zaire in 1971. It would again become the Democratic Republic of the Congo in 1997. The period between 1960 and 1964 is referred to as the First Congolese Republic.