Key events in Cuba's history under Fidel Castro:

Jan. 1, 1959 — Dictator Fulgencio Batista flees Cuba and Fidel Castro's rebels take power.

February 1960 — Soviet Deputy Prime Minister Anastas Mikoyan visits Cuba; signs sugar and oil deals, first of many pacts over next 30 years.

June 1960 — Cuba nationalizes U.S.-owned oil refineries after they refuse to process Soviet oil. Nearly all other U.S. businesses expropriated by October.

October 1960 — Washington bans exports to Cuba, other than food and medicine.

April 16, 1961 — Castro declares Cuba a socialist state.

April 17, 1961 — 1,297 Cuban exiles supported by CIA invade at Bay of Pigs; attack collapses two days later.

Jan. 22, 1962 — Cuba suspended from Organization of American States; Cuba responds with call for armed revolt across Latin America.

Feb, 7, 1962 — Washington bans all Cuban imports.

October 1962 — President Kennedy blockades Cuba to force removal of Soviet nuclear-armed missiles; Soviets agree within days and Kennedy agrees privately not to invade Cuba.

March 1968 — Castro's government takes over almost all private businesses other than small farms.

July 1972 — Cuba joins Comecon, Soviet-led economic bloc.

April 1980 — Refugee crisis starts at Mariel port as Cuba says will let anyone leave; some 125,000 flee by end of September.

December 1991 — Collapse of Soviet Union ends extensive aid to and trade with Cuba, whose economic output plunges 35 percent by 1994.

August 1994 — Castro declares will not stop Cubans trying to leave; some 40,000 take to sea heading for United States. Expanded U.S.-Cuba migration agreement signed in September.

October 1997 — Communist Party of Cuba holds fifth party congress; Castro reaffirms younger brother Raul Castro as successor.

Jan. 21-25, 1998 — Pope John Paul II visits Cuba.

June 23, 2001 — Castro faints briefly giving speech in searing sun, stunning Cubans and forcing many for first time to accept his eventual mortality.

Dec. 16, 2001 — Separate shipments of corn and frozen chicken arrive in Havana's harbor, representing first direct American food sales to Cuba in nearly 40 years.

March 6, 2003 — Cuba's parliament elects Castro to sixth 5-year term as president of Council of State, Cuba's supreme governing body.

March 18, 2003 — Cuban government announces crackdown on dissidents it accuses of working with American officials to undermine socialist system. Ultimately, 75 of Castro's most vocal critics sentenced to prison terms ranging from six to 28 years.

Oct. 20, 2004 — Castro accidentally trips and falls after speech, shattering left kneecap, breaking right arm and again underscoring advancing age and growing physical vulnerability.

July 31, 2006 — Castro relinquishes power to his brother before undergoing the first of several intestinal operations.