Fidel Castro Ruz was born in Birán, in the former province of Oriente, on August 13, 1926. Born into a well-off landowning family, he received his primary education in a rural school, later attended private Jesuit schools in Santiago de Cuba and Havana, and graduated from law school at the University of Havana.

While at university, he joined a student group against political corruption. He was a member of the Cuban People's Party (also known as the Orthodox Party) in 1947 and became a leader of its left wing. That same year, he volunteered for an armed expedition against the Trujillo dictatorship in the Dominican Republic (the expeditionaries were unable to leave Cuba to
carry out their plans). As a student leader, Fidel Castro was in Colombia to help organize a Latin American anti-imperialist student congress and participated in the April 1948 popular uprising in Bogotá.

After Fulgencio Batista's coup d'état of March 10, 1952, Fidel Castro began to organize a revolutionary organization to initiate armed insurrection against the US-backed Batista dictatorship. He organized and led an unsuccessful attack on the Moncada army garrison in Santiago de Cuba on July 26, 1953, for which he and over two dozen others were captured, tried, found guilty, and imprisoned; more than 60 revolutionaries were murdered by Batista's army during and immediately after the Moncada attack. While in prison, Fidel Castro edited his defense speech from the trial into the pamphlet "History Will Absolve Me," which was distributed in tens of thousands of copies and became the program of what was to become the July 26 Movement. Originally sentenced to 15 years, he and his comrades were released from prison 22 months later, in May 1955, as a result of a growing public campaign.

On July 7, 1955, Fidel Castro left for Mexico, where he began to organize a guerrilla expedition to Cuba to launch the armed insurrection. On December 2, 1956, along with 81 other fighters, including his brother Raúl, Che Guevara, Camilo Cienfuegos, Juan Almeida and Jesús Montané, Fidel reached the Cuban coast aboard the cabin cruiser Granma. For the next two
years, Fidel Castro directed the operations of the Rebel Army, in addition to continuing as central leader of the July 26 Movement. After an initial setback, the guerrillas were able to reorganize their forces and by late 1958 had successfully extended the struggle from the Sierra Maestra mountains to the heart of the island.

On January 1, 1959, Batista fled Cuba. In response to a call by Fidel, hundreds of thousands of Cubans launched an insurrectionary general strike that ensured the victory of the revolution. Fidel Castro arrived triumphantly in Havana on January 8 as commander-in-chief of Cuba's victorious Rebel Army. On February 13, 1959, he was named prime minister, a position he held until December 1976, when he became president of the Council of State and the Council of Ministers. He was the first secretary of the Central Committee of the Cuban Communist Party from its founding in 1965 until 2011.

On July 31, 2006, shortly before his 80th birthday, Fidel Castro handed over all his positions in the Cuban government and Communist Party to his brother Raúl, minister of defense and first vice-president of the Council of State.

Fidel Castro died on November 25, 2016.