Lucien E. Conein (1919-1998) was a U.S. clandestine operations officer working both for the Office of Strategic Services (OSS) and the Central Intelligence Agency (CIA). Among his many assignments, he was the direct U.S. contact to the 1963 coup against Ngo Dinh Diem.
He was a colorful character and a legend in special operations, often prefacing his stories with ""Now, this one is the double truth, scout's honor, the double truth," or "Don't believe anything I tell you; I'm an expert liar."
He was born in Paris, but brought up in Kansas City, sent there, alone, at the age of 5 by his widowed mother. He would grow up in Missouri with his aunt, a First World War French bride of an American soldier. Retaining his French citizenship, when the Second World War broke out, he went to the French Consulate in Chicago, and enlisted in 1939.
While growing up in Missouri, he retained his French citizenship, and when World War II began in 1939, he went to the French consulate in Chicago and joined the French Army. After the fall of France to Germany in 1940, he made his way back to the United States, joined the U.S. Army and, because of his fluency in French, was assigned to the OSS. As a member of Operation Jedburgh, which had missions similar to the guerrilla role of United States Army Special Forces, he landed behind German lines in Southern France in 1944. His resistance forces prepared the battlefield for attacks on retreating German forces.
While in France, he was made an honorary member of the Corsican Brotherhood. The threat of Corsica being annexed by Italy led to the Corsican groups being the most effective in the French Resistance. "When the Sicilians put out a contract, it's usually limited to the continental United States, or maybe Canada or Mexico. But with the Corsicans, it's international. They'll go anywhere. There's an old Corsican proverb: 'If you want revenge and you act within 20 years, you're acting in haste.'" With Conein, it might have been true; one never really knew.
In the 1945 OSS missions to China and North Vietnam, he had been assigned, as an expert guerrilla, fluent in French, and not in sympathy with French colonial policy, both to gather intelligence on French and Japanese positions, and to carry out sabotage in a program called COMORE.  Edward Lansdale said "he'd gotten in with some of the French and some of the Vietnamese who were anti-communist in those days . So he was a guy with the long-term memory of things and he was very close to the Foreign Legion and very close to some of the Vietnamese. Since the French Foreign Legion is literally that, he could not have been an actual Legionnaire, since he joined the French Army while a French citizen. While, in theory, he could have joined the Legion once he became a U.S. citizen, his service history is too well known to have allowed for that. What does make sense is that he became well-known to Legion personnel either in the late forties, or when he started stay-behind networks in 1954. The Legion, which lost a large number of its troops at Dien Bien Phu, was very active in the war against the Viet Minh.
1954 Saigon Military Mission
Conein, reporting to Lansdale in the Saigon Military Mission (SMM), arrived on July 1, 1945. Soon after, Conein, through William Rosson, set up a first planning meeting with Col Nguyen Van Vy, and the two SMM officers; Vy had seen his first combat in 1945 under Conein. 
In August, he went to Hanoi with the assignment of developing a paramilitary organization in the north. Its cover included arranging air transport for refugees to the South. As a C-46 transport, belonging to Civil Air Transport, a CIA proprietary airline, finished loading, they saw a small child standing on the ground below the loading door. They shouted for the pilot to wait, picked the child up and shoved him into the aircraft, which taxied away.
A Vietnamese man and woman ran up to Conein and his team, asking what they had done with their small boy, whom they'd brought out to say goodbye to relatives. Quickly, the team convinced the parents to fly to Free Vietnam and put them in the next aircraft to catch up with their son in Saigon.
Vy's group approached readiness in September.  On November 23, 23 agents and two cooks, the latter presumably honoring the brilliant Vietnamese-French culinary tradition, disguised themselves as coolies, were picked up from assembly points along the Saigon River, and, in the midst of the flow of refugee traffic, moved to their staging areas. They were ready in April 1955, and slipped ashore to their operational base in Haiphong. 
In 1958, Conein said that of the four Corsican airlines in Laos, only Air Laos Commerciale, run by Bonaventure "Rock" Francisci, was able to make a deal with Ngo Dinh Nhu to make daily airdrops of Laotian opium into South Vietnam. 
1963 Coup and aftermath
On July 9, 1963, when John McCone, Director of Central Intelligence briefed Kennedy on a coup being contemplated by the commander of the Army of the Republic of Viet Nam, Tran Van Don, who had discussed it with Conein.  Don was reported to have said the generals felt they had to act before the Viet Cong made more propaganda from the Buddhist persecution; Don said that Buddhist leaders did not believe Diem would keep his agreements made in June, and Buddhists were planning more suicides and demonstrations. Don then consulted Conein, "the only American I could really trust."
Neil Sheehan said "These men trusted Conein as they would not have trusted another CIA agent. He was an old comrade, and his French birth fortified the relationship. When he was with them, he saw that his French side came out, because he lived in both cultures in spirit and he knew that it put them at ease.
In October, Conein "accidentally" met General Don, who told him that a coup was nearly ready; the corps commander for the Saigon area had not yet committed. They scheduled another meeting for the 5th, at which, with Henry Cabot Lodge Jr. approval, Conein met with Gen. Duong Van Minh, the potential coup leader. Minh mentioned three possible plans; one involved assassination. When Conein reported back to Lodge, Lodge asked Washington that Conein "be authorized to say that the U.S. will not thwart a coup, that we are willing to review plans, and that we will continue support to a successor regime."
Conein stayed after the coup. In 1966, he observed that the "same professionals who organized corruption for Diem and Nhu were still in charge of police and intelligence.
Edward Lansdale had said he had met with Corsican gang leaders, whom had regarded him as a threat due to 1955 fighting between French intelligence and the CIA. Since they had made attempts on his life, he explained that his current brief did not include criminal investigation, and they agreed to a truce. Conein, however, fraternized with the Corsican underworld in Saigon, putting overall politicomilitary considerations beyond any counterdrug matters. McCoy suggests that this truce may, in part, have been a 1965-1967 attempt to avoid embarrassing Premier Nguyen Cao Ky. Conein told McCoy that when he left Vietnam, he was formally presented with a Corsican medallion that identified leaders, inscribed Per Tu Amicu Conein (for your friendship, Conein).
After retiring from the Army and CIA in 1968, he went back to South Vietnam as a businessman. In 1972, he joined the Drug Enforcement Administration to head their special operations, and was investigated by a committee under Senator Lowell Weicker, exploring but coming to no conclusions about DEA planning assassinations against drug traffickers. DEA involvement, however, was very edgy to the Corsican Brotherhood.
He told historian Stanley Karnow that he declined an offer from E. Howard Hunt, who had considered hiring him for the Watergate burglary, but observed, "If I'd been involved, we'd have done it right." Hunt testified to the Senate that he knew Conein.  Karnow spent 70 hours interviewing Conein for a potential biography, but gave up on the project when Karnow concluded that it was too hard for Conein to separate his cover stories from reality. Karnow said "He was the swashbuckling soldier of fortune -- the guy who has ceased to exist except in fiction. A marvelous storyteller. Whether the stories were true or not was beside the point. They were almost always almost entirely true." For example, it was rumored that he lost several fingers on a dangerous secret mission, possibly with the Legion. He had lost them when fixing the engine of the car in which he was taking the wife of his best friend to a tryst, so the mission was arguably secret and dangerous.
- Lucien E. Conein, Lieutenant Colonel, United States Army, Arlington National Cemetery Website
- McCoy, Alfred W.; Cathleen B. Read & Leonard P., II Adams (1972), The Politics of Heroin in Southeast Asia, Harper Colophon,p. 36
- Patti, Archimedes L. A (1980). Why Viet Nam?: Prelude to America's Albatross. University of California Press. , p. 113
- Gittinger, Ted (June 5, 1981), Oral History interview of Edward Lansdale, Lyndon Baines Johnson Presidential Library, pp. I-27 to I-29
- Document 95, Lansdale Team's Report on Covert Saigon Mission in 1954 and 1955,, at 573-83
- Gettleman, Marvin E.; Jane Franklin & Marilyn Young et al., Vietnam and America, Grove Press, ISBN 0802133622, p. 86
- Gittleman, p. 88, 91-92
- McCoy, p. 160
- John Prados, ed., DCI Briefing, July 9, 1963, JFK and the Diem Coup, vol. George Washington University Electronic Briefing Book No. 101
- Karnow, Stanley (1983), Vietnam, a History, Viking Press, pp. 283-284
- Sheehan, Neil. (1988), A bright shining lie: John Paul Vann and America in Vietnam, New Random House, pp. 362-363
- McCoy, p. 168
- McCoy, pp. 211-213
- Weiner, Tim (June 7, 1998), "Lucien Conein, 79, Legendary Cold War Spy", New York Times
- Testimony of E. Howard Hunt, U.S. Senate, Select Committee on Presidential Campaign Activities, September 24, 1973