Fidel Castro Ruz, Cuba's enduring "maximum leader," has held power since 1959. He is president (since 1976; formerly prime minister), first secretary of the Cuban Communist party, and commander of the armed forces. His decisions are final on matters of domestic and foreign policy.

Castro was born on Aug. 13, 1926 (some sources give 1927), on a farm in Mayari municipality in the province of Oriente. He attended good Catholic schools in Santiago de Cuba and Havana, where he took to the spartan regime at a Jesuit boarding school, Colegio de Belen. In 1945 he enrolled at the University of Havana, graduating in 1950 with a law degree. He married Mirta Diaz-Balart in 1948, but they were divorced in 1954. Their son, Fidel Castro Diaz-Balart, born in 1949, has served as head of Cuba's atomic energy commission. A member of the social-democratic Ortodoxo party in the late 1940s and early 1950s, Castro was an early and vocal opponent of the dictatorship of Fulgencio BATISTA. On July 26, 1953, Castro led an attack on the Moncada army barracks that failed but brought him national prominence. At the time, his political ideas were nationalist, antiimperialist, and reformist; he was not a member of the Communist party.

Following the attack on Moncada, Castro was tried and sentenced to 15 years in prison but was amnestied in 1955. He then went into exile in Mexico, where he founded the 26th of July Movement, vowing to return to Cuba in order to fight against Batista. In December 1956, he and 81 others, including Che GUEVARA, returned to Cuba and made their way to the Sierra Maestra mountains, from which they launched a successful guerrilla war. Castro proved himself a strong leader; he also demonstrated shrewd political skills, convinced that he had a historic duty to change the character of Cuban society. Seeing his army collapse, and unable to count on the support of the United States, Batista fled on Jan. 1, 1959, paving the way for Castro's rise to power.

In its early phase, Castro's revolutionary regime included moderate politicians and democrats; gradually, however, its policies became radical and confrontational. Castro remained the unchallenged leader, and the masses--whose living conditions he improved--rallied behind him. Promises of elections were unfulfilled, foreign-owned properties confiscated, and opponents of the regime killed or driven into exile. Thousands of middle-class and professional Cubans left the island once it became clear that a Communist revolution was under way.

The U.S.-supported BAY OF PIGS INVASION failed (1961), and Castro was able to consolidate his power. In December 1961 he publicly declared that "I have been a Marxist-Leninist all along, and will remain one until I die." Cuba aligned itself with the Soviet Union, which granted Cuba massive economic, technical, and military assistance. In 1962 the CUBAN MISSILE CRISIS dramatized the Cuban-Soviet alliance. In 1979 he was elected chairman of the Nonaligned Nations Movement, a position that gained him some international prestige. Castro believes that he has a revolutionary duty to fight imperialism in the developing world; he dispatched troops to assist Marxist regimes in Angola and Ethiopia. He remains a caustic critic of U.S. foreign policy.

Castro, who has no rivals for power, demands the absolute loyalty of those around him. He has been less than successful as an economic policymaker: Cuba remains a poor country in debt whose livelihood depends on sugar production. He nonetheless holds the system in place. His greatest achievement is the consolidation of a Communist regime in the Caribbean, so close to Cuba's main antagonist. In no small measure, the Cuban revolution is still Castro's revolution.