Cuba invaded Angola in late 1975 to save the MPLA from a South African–backed offensive, in a decision taken by Fidel Castro against the initial counsel of Moscow. Within four months, Havana had deployed roughly 36,000 troops, organized as five brigades and dozens of air-defense and tank battalions. The Cuban operation, code-named Carlota after a nineteenth-century Cuban independence heroine, was the largest deployment of Cuban soldiers abroad in the country’s history and the largest Soviet-bloc military intervention in Africa during the Cold War.
The proximate trigger was the South African invasion. In September 1975, the apartheid regime’s Defence Force crossed into southern Angola under the cover of a fiction about “technical assistance” to UNITA, advancing on the capital of Luanda and the oil-rich exclave of Cabinda. At the same time, Zaire’s Mobutu, supported by the CIA, was arming the FNLA for a thrust from the north. By October 1975, the MPLA — which had taken Luanda at independence on November 11, 1975 — was fighting for its life. Agostinho Neto’s personal plea to Castro produced the response.
Gleijeses’s Conflicting Missions (2002) — drawing on Cuban Politburo minutes, Soviet Politburo archives, and South African military records — has shown that the Cuban decision was taken in opposition to Soviet advice. Moscow was reluctant: Brezhnev and Defense Minister Andrei Grechko wanted to avoid a direct clash with the United States and South Africa. Castro was determined. As he told the Cuban Politburo on November 5, 1975, “We are going to Angola, whatever the cost, to prove that the imperialist aggression in Angola cannot be resolved without the participation of Cuba.”
Cuban foreign-policy objectives in Angola were three. First, a defense-of-revolution imperative: the MPLA was a long-standing Cuban ally since 1965, and its defeat would have ended the only revolutionary state in southern Africa. Second, an internationalist doctrine — formalized in Castro’s 1967 “Message to the Peoples of the World” and the 1974 “Speech on Internationalism” — that small socialist states should commit resources to anti-colonial struggle out of solidarity. Third, a strategic calculation: Angola offered Cuba a continental foothold that compensated for its small size and isolation in the Caribbean.
The Soviet Union paid the bill. By the 1980s, the cost of sustaining Cuba’s military and civilian presence in Angola — at its peak, around 50,000 troops plus 30,000 Cuban civilian advisers — was running at roughly $5 million a day, almost entirely subsidized by Moscow. The intervention secured Luanda, helped establish the MPLA as the government of Angola, and signaled to the rest of Africa that the Soviet–Cuban alliance had both reach and will to use it. For a broader account, see the Angolan Civil War article.