Emmanuel "Manno" Charlemagne was the voice and conscience of Haiti's impoverished masses, a revolutionary protest singer and folk-hero in the majority-black French- and Creole-speaking nation.

Armed with his deep melodious voice, firebrand lyrics and acoustic Takamine guitar, Mr. Charlemagne, who died at 69 on Dec. 10 in Miami Beach, was credited with helping build popular resistance to the decades-long Duvalier dictatorship and Haiti's later military juntas. His popularity propelled him to become mayor of the capital, Port-au-Prince, representing around 2.5 million people, almost a quarter of Haiti's overall population.

Singing in French or the local Creole — based on the phonetic pronunciation of French by African slaves — he was often described as Haiti's Bob Marley for the power of his lyrics, although his guitar and singing style was influenced more by the great 20th century French-language chansonniers such as Georges Brassens and the Belgian balladeer Jacques Brel. His lyrics leaned on parables and metaphors that conveyed the rage and despair of those who lived in the Western Hemisphere's poorest nation and were led by a series of thuggish governments.

"In a country where many people can't read, the singer becomes journalist, newscaster, keeper of the collective memory," jazz critic and composer Fernando Gonzalez once wrote in the Boston Globe of Mr. Charlemagne's influence.

Targeted by assassins, jailed multiple times and forced into exile twice for his democratic views and activism for human rights, Mr. Charlemagne called himself an "anti-imperialist singer." He sang against le blanc (the white man); not white people in general, more in the way American Indians speak of "the white man." His music also criticized the colonialists, in Haiti's case white French as well as the later wealthy mulatto (mixed race) elite that long ran the country.

Mr. Charlemagne first gained attention singing about the corruption and violence of the almost three-decade Duvalier regime, first that of François "Papa Doc" Duvalier and later that of his son Jean-Claude "Baby Doc," both of whom ruled through fear and became mega-wealthy while most of their people starved.

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His lyrics less-than-subtly attacked the Duvaliers' hygiene and mocked the notorious Tonton Macoute (the boogeymen), the Duvaliers' private militia known for their straw hats, sunglasses, guns, machetes and ruthlessness against compatriots. The Macoute killed thousands of civilians during the Duvalier dynasty, and anyone caught listening to Mr. Charlemagne's songs — mostly on clandestine tape cassettes — could be thrown into the horrific Fort Dimanche prison in Port-au-Prince.

One of his most famous post-Duvalier songs was "La Fimen" ("The Smoke"), in which he tells the military junta of the time, "You are nothing but smoke. And you, too, will disappear when the people stand up and open the windows."

He spent months in prison and when released was banned from singing. But he continued to perform in secret venues, often attracting thousands of Haitians.

Even after Jean-Claude Duvalier fled to France on a U.S. military plane on Feb. 7, 1986, Mr. Charlemagne was hunted by the ensuing military regimes including one led by Lt. Gen. Raoul Cédras, who in 1991 had ousted the democratically elected president Jean-Bertrand Aristide, for whom the entertainer had enthusiastically campaigned.

Under Cédras, Mr. Charlemagne took refuge in the Argentine embassy in Port-au-Prince until he was released after an international campaign spearheaded by American filmmaker Jonathan Demme, who made acclaimed documentaries about Haiti and also included Mr. Charlemagne on his 1989 musical compilation album "Konbit: Burning Rhythms of Haiti."

"He's just got a heartbreakingly beautiful, fantastically communicative voice," Demme told NPR years later. "Had Manno not been this guy, who for whatever reasons, channeled his art into the circumstances of the people, Manno would be as famous as anybody."

Demme's intervention drew widespread celebrity support, and Mr. Charlemagne was allowed into exile in Argentina and later Miami until he was able to return to his homeland after the return of democracy. The singer subsequently split his time between Haiti and Miami, where he attracted many a tourist to the popular and colorful Tap Tap Haitian restaurant/bar in Miami Beach. Many of his later songs questioned the genitalia measurements of the would-be democratic Haitians politicians.

Ed Lozama, a South Florida radio personality who heads the Haitian government-owned National Radio in the capital, told the Miami Herald that Mr. Charlemagne was "the conscience of the nation during the transition from dictatorship to democracy. As he fought the dictator, he warned the new leadership about the temptation of getting back to the old days."

Mr. Charlemagne later sang songs defending Haitians in their diaspora — mostly in New York, Montreal or Miami. One of his best-known songs in Creole, titled "Alyenkat" (Alien Card), attacked U.S. authorities' treatment of Haitian political or economic "boat people" seeking refuge in a nation that had invaded or intervened in their own country on several occasions during the 20th century.

Joseph Emmanuel Charlemagne was born April 14, 1948, in the poverty-stricken Carrefour district on the edge of Port-au-Prince. He was 9 when his mother, a singer, left home to work in Miami as a maid. The boy was left in the care of an aunt; he never knew his father.

Influenced by the folk/slavery songs of peasants who moved from the countryside to Carrefour, and by the songs of his Catholic school choir, he took up singing and the guitar in his teens and formed a band called Les Remarquables.

He began releasing albums in the late 1970s during a fleeting reprieve toward artists, thanks to outside pressures on the Duvalier regime. But it was not long before he was again arrested, including once while performing onstage.

In an authoritarian state, he often said, it is inevitable that artists will become dangerous. "The role of the artist is to reflect society so artists have to make a decision if they are going to collaborate with or challenge authority," he told the Globe in 1992. "I think of Victor Jara in Chile; I think of Violeta Parra, Mercedes Sosa. . . . Popular music in Haiti has always been the music of struggle, so most of the time politics play a key part in my work."

His later tenure as mayor, from 1995 to 1999, was turbulent. He lacked administrative skills as well as the money to improve sanitation, the education system and other problems long plaguing the municipality. He also was, by many accounts, temperamentally unsuited to the job; he could be undiplomatic with other leaders and fell out of favor with Aristide, his former ally.

Survivors include his wife, the former Immacula Joseph; children from several relationships; and his sister, Katia Barnave, who confirmed the death.

In a 1995 interview, after he had been elected mayor by a landslide against the incumbent, the Times asked Mr. Charlemagne whether he might later run for president. "Me, no way," he replied. "I love to protest, and I can't protest as president. As president, you are the guy that people are always focusing on, and I prefer to be the guy down here, pointing his finger."