Prominent Haitian intellectual and politician Gerard Pierre-Charles died in Cuba Sunday of heart failure. He was 68.

Involved in politics for half a century, Pierre-Charles was an economist who wrote 16 books and a longtime communist whose ideology shifted toward the center after the fall of the Berlin Wall in 1989.

He was a leading opponent of his former ally President Jean-Bertrand Aristide up until his ouster in February, accusing him of betraying the poor and drifting toward dictatorship.

Though he never held elected office, Pierre-Charles became a top leader of the Democratic Convergence, an alliance that held a series of protests until Aristide left amid a rebellion this year.

In 1959, Pierre-Charles helped found the Party of Popular Understanding, which later was absorbed into the Haitian Communist Party. Communists faced persecution under dictator Francois “Papa Doc” Duvalier, and in 1960 Pierre-Charles began 26 years in exile, studying economics at Mexico’s Nation al Autonomous University.

As an economics professor, he became known for works on Haiti and Latin American economics. His book “X-ray of a Dictatorship,” first published in Spanish in 1969, analyzed repression under Duvalier.

Pierre-Charles returned to Haiti in 1986 after an uprising toppled Jean-Claude “Baby Doc” Duvalier.

For years he was allied with Aristide, who became Haiti’s first freely elected president in 1990. Pierre-Charles stood by him through his 1991 ouster and his 1994 restoration to power by U.S. troops.

The two had a falling out in 1997, when Pierre-Charles accused the former priest of trying to monopolize power. Pierre-Charles stepped up criticism after Aristide was elected to a second term in 2000. In 2001, Aristide backers burned down Pierre-Charles’s home, his research center, and party office.

Pierre-Charles’s supporters gathered signatures to nominate him for the Nobel Peace Prize last year.