François Duvalier (April 14, 1907 – April 21, 1971), was the President of Haiti from 1957 to his death.

Duvalier first won acclaim in fighting diseases, earning him the nickname "Papa Doc" ("Daddy Doc[tor]" in French). He opposed a military coup d'état in 1950, and was elected President in 1956 on a populist and black nationalist platform. His rule, based on a purged military, a rural militia and the use of a personality cult and voodoo, resulted in a brain drain from which the country has not recovered. Ruling as President for Life since 1964, he was succeeded by his son, Jean-Claude Duvalier, nicknamed "Baby Doc".

Duvalier was born in Port-au-Prince, the son of Duval Duvalier, a justice of the peace, and Ulyssia Abraham, a baker. As his mother was mentally unstable and lived in an asylum until her death in 1921, Duvalier was largely raised by an aunt. Duvalier completed a degree in medicine from the University of Haiti in 1934. He served as staff physician at several local hospitals. He spent a year at the University of Michigan studying public health. In 1943, he became active in a U.S.-sponsored campaign to control the spread of contagious tropical diseases, helping the poor to fight typhus, yaws, malaria and other tropical diseases that ravaged Haiti for years. His patients affectionately called him "Papa Doc", a moniker that he would use throughout his life.

Lucky enough to be schooled and literate in a country where all but a tiny handful were uneducated, Duvalier witnessed the political turmoil of his country. The invasion and occupation of U.S. Marines on Haitian soil in 1915, followed by incessant violent repressions of political dissent, and American-installed puppet rulers, left a powerful impression on the young Duvalier. He was also aware of the latent political power of the poor black majority and their resentment against the tiny mulatto elite. Duvalier became involved in the négritude movement of Haitian author Dr. Jean Price-Mars. He began an ethnological study of Vodou, Haiti's native religion, that would later pay enormous political dividends. In 1938, Duvalier co-founded the journal Les Griots.

In 1939 Duvalier married Simone Ovide, with whom he had four children: Marie Denise, Nicole, Simone and Jean-Claude, their only son.

In 1946, Duvalier aligned himself with President Dumarsais Estimé and was appointed director general of the National Public Health Service. In 1949, Duvalier served as minister of both health and labour but when General Paul Magloire ousted President Estimé in a coup d'état, Duvalier left the government and was forced into hiding until an amnesty was declared in 1956. In December 1956, Magloire resigned and left Haiti to be ruled by a succession of provisional governments. On September 22, 1957, presidential elections pitted Louis Déjoie, a mulatto land-owner and industrialist from the north of Haiti, against Duvalier, who was backed by the military. Duvalier campaigned as a populist leader, using a noiriste strategy of challenging the mulatto elite and appealing to the Afro-Haitian majority. He described his opponent as part of the ruling mulatto class that was making life difficult for the country's rural black majority. The election resulted in Duvalier defeating Déjoie with 678,860 votes. Déjoie polled 264,830 votes, independent candidate Jumelle a mere percentage of the electorate. Duvalier's only opponent among the Black proletarians, Daniel Fignole, had been forcibly exiled before election, thus leaving Duvalier a path for a landslide. After being sworn in on October 22, Duvalier exiled most of the major supporters of Déjoie and had a new constitution adopted in 1957.

President Duvalier promoted and patronised members of the black majority in the civil service and the army. In mid-1958, the army, which had supported Duvalier earlier, tried to oust him in another coup but failed. In response, Duvalier replaced the chief of staff with a more reliable officer and then proceeded to create his own power base within the army by turning the army's Presidential Guard into an elite corps aimed at maintaining Duvalier's power. After this, Duvalier dismissed the entire general staff and replaced it with officers owing their positions and their loyalty to him. In 1959, he also created a rural militia, the Milice Volontaires de la Sécurité Nationale (MVSN, English: National Security Volunteers), commonly referred to as the Tonton Macoutes after a Creole term for the bogeyman, to extend and bolster support for the regime in the countryside. The Macoutes, which by 1961 had twice the numbers of the regular army, never developed into a real military force but still was more than a mere secret police. In the name of nationalism, Duvalier expelled almost all of Haiti's foreign-born bishops, an act that earned him excommunication from the Catholic church. In 1966, Duvalier managed to persuade the Holy See to allow him to nominate the Catholic hierarchy for Haiti.

On May 24, 1959, Duvalier suffered a massive heart attack, possibly as a result of an insulin overdose; he had been a diabetic since early adulthood and also suffered from heart disease and associated circulatory problems. During this heart attack he was unconscious for nine hours; many associates believed that he suffered neurological damage during these events that affected his mental health and made him paranoid. While recovering, Duvalier left power in the hands of Clement Barbot, leader of the Tonton Macoutes. Upon his return, Duvalier accused Barbot of trying to supplant him as president and had him imprisoned. In April, 1963, Barbot was released and began plotting to remove Duvalier from office by kidnapping his children. The plot failed and Duvalier subsequently ordered a massive search for Barbot and his fellow conspirators. When during the search Duvalier was told that Barbot had transformed himself into a black dog, Duvalier ordered that all black dogs in Haiti be put to death. Barbot was later captured and shot by the Tonton Macoutes in July, 1963. In other incidents, Duvalier ordered the head of an executed rebel to be packed in ice and brought to him to allow him to commune with the dead man's spirit.

In 1961, he began violating the provisions of the 1957 constitution: first he replaced the bicameral legislature with a unicameral body. Then he called a new presidential election, though his term was to expire only in 1963 and the constitution prohibited reelection. The election, in which he was the sole candidate, resulted in an official tally of 1,320,748 votes to zero. Upon hearing the results of the election, Duvalier proclaimed: "I accept the people's will. As a revolutionary, I have no right to disregard the will of the people." The New York Times commented: "Latin America has witnessed many fraudulent elections throughout its history but none has been more outrageous than the one which has just taken place in Haiti." On June 14, 1964, a blatantly rigged constitutional referendum made "President for Life", a title previously held by seven Haitian presidents. An implausible 99.9 percent voted in favor, and all ballots were premarked "yes." The new document granted Duvalier--or "Le Souverain," as he was called--absolute powers as well as the right to name his successor.

His relationship with the United States proved difficult. In his early years, Duvalier often rebuked the United States for its friendly relations with the Dominican dictator Rafael Trujillo (killed in 1961), while leaving Haiti, "the poor negro Republic out in the cold". The Kennedy administration (1961/63) was particularly disturbed by Duvalier's repressive and authoritarian rule and allegations that he misappropriated aid money, then a substantial part of the Haitian budget, and a Marine mission to train Tonton Macoutes. Acting on the charges, Washington cut off most of its economic assistance in mid-1962, pending stricter accounting procedures which Duvalier refused. Duvalier publicly renounced all aid from Washington on nationalist grounds, portraying himself as a "principled and lonely opponent of domination by a great power." Duvalier misappropriated millions of USD of international aid, including 15 millions USD annually from the United States. He transferred those money to personal accounts. Another Duvalier's method to obtain foreign money was to gain foreign loans, including 4 million USD from Cuban president Fulgencio Batista. Duvalier also organized forced blood transfusion on a mass scale. He eventually sent the blood to the transfusion stations in the United States.

After Kennedy's assassination in November 1963 - which Duvalier later claimed resulted from a curse that he had placed on him, the U.S. eased its pressure on Duvalier, grudgingly accepting Duvalier as a bulwark against communism. Duvalier skillfully exploited tensions between the United States and Cuba, emphasizing his anti-communist credentials and Haiti's strategic location as a means of winning U.S. support. Duvalier enraged Fidel Castro of Cuba by voting against the country in a OAS meeting and subsequently at the UN where a trade embargo was imposed on Cuba. Cuba answered by breaking off diplomatic relations and Duvalier subsequently instituted a campaign to rid Haiti of communists.

Duvalier's relationship with the neigbouring Dominican Republic were always tense: in his early years, Duvalier emphasised the differences between the two countries. In April 1963, relations were brought to the edge of war by the political enmity between Duvalier and the Dominican president Juan Bosch. Bosch, a left-leaning Democrat, provided asylum and support to Haitian exiles who plotted against the Duvalier regime. Duvalier ordered his Presidential Guard to occupy the Dominican Embassy in Pétionville, aiming at apprehending an army officer believed to have been involved in Barbot's plot to kidnap Duvalier's children. The Dominican president reacted with outrage, publicly threatened to invade Haiti, and ordered army units to the frontier. However, as Dominican military commanders expressed little support for an invasion of Haiti, Bosch refrained from the invasion and settled for a mediation by the OAS.

Duvalier also supported Pan-African ideals.

Duvalier's government was soon accused of being one of the most repressive in the hemisphere. Within the country, Duvalier used both political murder and expulsion to suppress his opponents; estimates of those killed are as high as 30,000. Attacks on Duvalier from within the military were treated as especially serious. When bombs were detonated near the Presidential Palace in 1967, Duvalier had nineteen Presidential Guard officers shot in Fort Dimanche. A few days later Duvalier had a public speech during which he read the "attendance sheet" with names of all 19 killed officers. After each name he said "absent". After reading the whole list Duvalier remarked "All were shot." Haitian communists and suspected communists, in particular, bore the brunt of the government's repression. Duvalier targeted them both as a means to secure U.S. support as a bulwark against Communist Cuba and on principle: Duvalier had personally been exposed to communist and leftist ideas early in his life and rejected them. On April 28, 1969, Duvalier instituted a campaign to rid Haiti of all communists, promulgating a law stipulating that "Communist activities, no matter what their form, are hereby declared crimes against the security of the State," and prescribing the death penalty for individuals prosecuted under this law. Duvalier employed intimidation, repression and patronage to supplant the old mulatto elites with a new elite of his own making. Corruption — in the form of government rake-offs of industries, bribery, extortion of domestic businesses, and stolen government funds — enriched the dictator's closest supporters. Most of these supporters held sufficient power to enable them to intimidate the members of the old elite who were gradually co-opted or eliminated. Educated professionals fled Haiti in droves for New York City, Miami, French-speaking Montreal, Paris, and several French-speaking African countries, exacerbating an already serious lack of doctors and teachers. Some of the highly skilled professionals joined the ranks of several UN agencies to work in development in newly-independent nations such as Ivory Coast, and Congo. The country has never recovered from this brain drain. The government confiscated peasant land holdings to be allotted to members of the militia, who had no official salary and made their living through crime and extortion. The dispossessed swelled the slums by fleeing to the capital to seek meagre incomes to feed themselves. Malnutrition and famine became endemic. Most of the aid money given to Haiti was spent improperly.

Nonetheless, Duvalier enjoyed significant support among Haiti's majority black rural population who saw in him a champion of their claims against the historically dominant mulatto élite. During his fourteen years in power, he created a substantial black middle class, chiefly through government patronage. Duvalier also initiated the development of Mais Gate Airport, now known as Toussaint Louverture International Airport. Duvalier fostered a personality cult around himself, and claimed to be the physical embodiment of the island nation. He also started to revive the traditions of vodou, later on using them to consolidate his power as he claimed to be a houngan, or vodou priest himself. In an effort to make himself even more imposing, Duvalier deliberately modeled his image on that of Baron Samedi. He often donned sunglasses to hide his eyes and talked with the strong nasal tone associated with the loa. The Duvalier regime propaganda even stated that "Papa Doc: was one with the loas, Jesus Christ, and God himself". The most celebrated image from the time shows a standing Jesus Christ with hand on a seated Papa Doc's shoulder with the caption "I have chosen him". There was even a Duvalierist variant of the Lord's Prayer. Duvalier also held in his closet the head of his former opponent Blucher Philogenes who tried to overthrow him in 1963. Duvalier held night conversations with the head.

Duvalier held Haiti in his grip until his death in early 1971. His 19-year-old son Jean-Claude Duvalier, nicknamed "Baby Doc", succeeded as president.