Mercenary
During the crisis, mercenaries were employed by various factions, and also at times helped the United Nations and other peace keepers.
In 1960 and 1961, Mike Hoare worked as a mercenary commanding an English-speaking unit called "4 Commando" supporting a faction in Katanga, a province trying to break away from the newly independent Congo under the leadership of Moïse Tshombe. Hoare chronicled his exploits in his book the Road to Kalamata.
In 1964, Tshombe (then Prime Minister of Congo) hired Major Hoare to lead a military unit called "5 Commando" made up of about 300 men, most of whom were from South Africa. The unit's mission was to fight a rebel group called Simbas, who already had captured almost two-thirds of the country.
In Operation Dragon Rouge, "5 Commando" worked in close cooperation with Belgian paratroopers, Cuban exile pilots, and CIA hired mercenaries. The objective of Operation Dragon Rouge was to capture Stanleyville and save several hundred civilians (mostly Europeans and missionaries) who were hostages of the Simba rebels. The operation saved many lives; however, the Operation damaged the reputation of Moïse Tshombe as it saw the return of white mercenaries to the Congo soon after independence and was a factor in Tshombe's loss of support from president of Congo Joseph Kasa-Vubu who dismissed him from his position
At the same time Bob Denard commanded the French-speaking "6 Commando", "Black Jack" Schramme commanded "10 Commando" and William "Rip" Robertson commanded a company of anti-Castro Cuban exiles.
Later, in 1966 and 1967, some former Tshombe mercenaries and Katangese gendarmes staged the Mercenaries' Mutinies.

Biafra: Mercenaries fought for Biafra in the Fourth Commando Brigade led by Rolf Steiner during the Nigerian Civil War (1967–1970). Other mercenaries flew aircraft for the Biafrans. In October 1967, for example, a Royal Air Burundi DC-4M Argonaut, flown by mercenary Heinrich Wartski, also known as Henry Wharton, crash-landed in Cameroon with military supplies destined for Biafra.
It was hoped that employing mercenaries in Nigeria would have similar impact to the Congo, but the mercenaries proved largely ineffective. The British historian Philip Baxter wrote the principle difference was that the Congolese militias commanded by leaders with almost no military experience were no match for the mercenaries, and by contrast the Sandhurst-trained Nigerian Army officers were of an "altogether higher caliber" than Congolese militia leaders. Through much of the leadership of the Nigerian Army had been killed in two coups in 1966, there were still just enough Sandhust graduates left in 1967 to hold the Nigerian Army together and provide enough of a modicum of military professionalism to defeat the mercenaries. By October 1967, most of the mercenaries who had been expecting easy victories like those won in the Congo had already left Biafra, complaining that the Nigerians were a much tougher opponent who were defeating them in battle.
When asked about the impact of the white mercenaries, General Philip Effiong, the chief of the Biafran general staff replied: "They had not helped. It would have made no difference if not a single one of them came to work for the secessionist forces. Rolf Steiner stayed the longest. He was more of a bad influence than anything else. We were happy to get rid of him." One Biafran officer, Fola Oyewole, wrote about the sacking of Steiner in late 1968: "Steiner's departure from Biafra removed the shine from the white mercenaries, the myth of the white man's superiority in the art of soldering". Oyewole wrote that the white mercenaries were hated by the ordinary people of Biafra due to their high-handed behavior; a tendency to retreat when it appeared possible the Nigerians were about to cut them off instead of holding their ground; and a fondness for looting, noting that the European mercenaries seemed more interested in stealing as much as possible instead of helping Biafra."
In May 1969, Count Carl Gustaf von Rosen formed a squadron of five light aircraft known as the Babies of Biafra, which attacked and destroyed Nigerian jet aircraft on the ground and delivered food aid. Count von Rosen was assisted by ex-RCAF fighter pilot Lynn Garrison.

Angola: In 1975, John Banks, an Englishman, recruited mercenaries to fight for the National Liberation Front of Angola (FNLA) against the Popular Movement for the Liberation of Angola (MPLA) in the civil war that broke out when Angola gained independence from Portugal in 1975. In the United States, David Bufkin, a self-proclaimed mercenary hero started a recruiting campaign in Soldier of Fortune magazine calling for anti-Communist volunteers, especially Vietnam veterans, to fight in Angola as mercenaries, claiming to be funded to the tune of $80,000 by the Central Intelligence Agency. Bufkin was in fact a former U.S. Army soldier "who has gone AWOL several times, has been tried for rape, and been in and out of jail several times", did not have $80,000, was not supported by the CIA, instead being a con-man who had stolen most of the money paid to him. Bufkin managed to get a dozen or so American mercenaries to Angola, where several of them were killed in action with the rest being captured.
One of the leaders of the mercenaries was Costas Georgiou (the self-styled "Colonel Callan"), who was described by the British journalist Patrick Brogan as a psychopathic killer who personally executed fourteen of his fellow mercenaries for cowardice, and who was extremely brutal to black people. Within 48 hours of his arrival in Angola, Georgiou had already led his men in disarming and massacring a group of FNLA fighters (his supposed allies), who he killed just for the "fun" of it all. At his trial, it was established that Georgiou had personally murdered at least 170 Angolans. Inept as a military leader as he was brutal, Georgiou notably failed as a commander. It was believed in 1975–76 that recruiting white mercenaries to fight in Angola would have a similar impact that the mercenaries had in the Congo in the 1960s, but in Angola the mercenaries failed completely as Brogan described their efforts as a "debacle". If anything, the white mercanaries with their disdain for blacks, or in the case of Georgiou murderous hatred seemed to have depressed morale on the FNLA side.
Many of the mercenaries in Angola were not former professional soldiers as they claimed to have been, but instead merely fantasists who had invented heroic war records for themselves. The fantasist mercenaries did not know how to use their weapons properly, and often injured themselves and others when they attempted to use weaponry that they did not fully understand, leading to some of them being executed by the psychopathic killer Georgiou who did not tolerate failure. On 27 January 1976, a group of 96 British mercenaries arrived in Angola and within a week about dozen had accidentally maimed themselves by trying to use weapons that they falsely claimed to be proficient with. The MLPA forces were better organized and led, and the dispatch of 35, 000 Cuban Army troops in November 1975 decided the war for the MLPA. Cuban accounts of the Angolan war speak of the efforts of the mercenaries in a tone of contempt as Cuban veterans contend that the mercenaries were poor soldiers who they had no trouble defeating.
When captured, John Derek Barker's role as a leader of mercenaries in Northern Angola led the judges to send him to face the firing squad. Nine others were imprisoned. Three more were executed: American Daniel Gearhart was sentenced to death for advertising himself as a mercenary in an American newspaper; Andrew McKenzie and Costas Georgiou, who had both served in the British Army, were sentenced to death for murder. Georgiou was shot by firing squad in 1976. Costas' cousin Charlie Christodoulou was killed in an ambush.
Executive Outcomes employees, Captains Daniele Zanata and Raif St Clair (who was also involved in the aborted Seychelles Coup of 1981), fought on behalf of the MPLA against the National Union for the Total Independence of Angola (UNITA) in the 1990s in violation of the Lusaka Protocol.

The Comoros coup: A major aim of French foreign policy was and still is to maintain the French sphere of influence in what is called Françafrique. In 1975, Ali Soilih took power in the Comoros via a coup, and proved unwilling to accept the French viewpoint that his nation was part of Françafrique. Unhappy with Soilih, the French secret service, the Service de Documentation Extérieure et de Contre-Espionnage in 1978 hired the French mercenary Bob Denard to invade the Comoros to overthrow Soilih. Making the Comoros a tempting target for Denard were its small size, consisting of only three islands in the Indian Ocean. Moreover, Soilih had abolished the Comorian Army, replacing the Army with a militia known as the Moissy, made up mostly of teenage boys with only the most rudimentary military training.