Timeline: Cuba and U.S. relations through the years

1959 – Fidel Castro becomes the leader of Cuba after leading an armed revolt to overthrow Cuban dictator Fulgencio Batista.

1960 – The U.S. implements an economic embargo against Cuba, that remains to this day.

April 1961 – Cuban exiles trained by the Central Intelligence Agency attempt to overthrow Castro's dictatorship in the failed Bay of Pigs invasion.

1961 – Undeterred by the failed invasion, the Kennedy administration implements Operation Mongoose to destabilize the Cuban government and economy. The operation includes plans to assassinate Castro.

October 1962 – The Cuban Missile Crisis causes panic, as America seems on the brink of nuclear war with the Soviet Union. An American U-2 spy plane photographs nuclear missile sites being built in Cuba by the Soviets.

Fearing an invasion from Americans, Castro allows the Soviet Union to place missiles on Cuban soil. The crisis is resolved when the Soviets pledges to remove the missiles in exchange for the U.S. removing missiles in Turkey.

1980 – After the Cuban government opens its coast for anyone to leave with a permit, nearly 125,000 Cubans flee to the USA. The U.S. Coast Guard refers to the influx of Cuban immigrants as the "1980 Cuban Exodus."

1993 – Facing economic turmoil, socialist Cuba opts to legalize the U.S. dollar, privately owned business and services, and allows farmers to sell some produce privately rather than to the state.

In October, Cuba accuses the U.S. of tightening the economic embargo and depriving Cubans of medicine and other resources.

1994 – Cuba and the U.S. come to an immigration agreement that the U.S. will accept 20,000 Cubans annually, contingent that the Cuban government controls the exodus of Cuban refugees.

PHOTOS: Cuba through the years

1996 – After two U.S. civilian planes are shot down by Cuban air force jets, Congress further tightens the Cuban trade embargo.

1997 – The Clinton administration approves licenses for U.S. news organizations to open bureaus in Cuba.

1998 – An executive order from the Clinton administration allows sales of some food and agricultural products to Cuba.

January 1998 – Pope John Paul II visits Cuba and calls for political and social reform. The visit marks the first time a pope has visited the country and the first time a pope was welcome after Castro rose to power in 1959.

Nov. 25, 1999 – A 6-year-old Cuban boy is rescued off the coast of Florida after the boat his mother and others are traveling in capsizes. Elian Gonzalez becomes the subject of an international custody battle as his uncle and relatives in Miami fight with his father and the Cuban government over where the boy should live.

2000 – Armed U.S. federal agents seize Elian Gonzalez from his relatives in Miami. The boy is returned to his father after a lengthy custody battle.

2001 – After Hurricane Michelle slams the Cuban coast, the U.S. exports food to Cuba for the first time in 40 years.

January 2002 – First Afghan prisoners arrive at the U.S. Guantanamo Bay Naval Station in Cuba.

May 2002 – The Bush administration accuses the Cuban government of developing biological weapons.

2006 – Congressional advocates of easing restrictions to Cuba fly to Havana hoping to meet with Acting President Raúl Castro, but are turned away.

2008 – Raúl Castro officially becomes president of Cuba.

April 2009 – President Obama eases travel restriction to Cuba.

December 2009 – Alan Gross, a U.S. citizen and State Department subcontractor, is detained in Cuba and accused of spying.

October 2011 – The U.S. releases Cuban agent Rene Gonzalez from a Florida jail. He was part of a group known as the Cuban Five, convicted of spying and sentenced to prison in 2001 in the U.S.

December 2013 – President Obama and Raúl Castro meet at the Nelson Mandela memorial service. The handshake appears to be the second U.S.-Cuban leader handshake in the last five decades.

February 2014– Poll finds most Americans favor normalizing relations with Cuba.

Dec. 16 – The United States and Cuba swap prisoners.

Dec. 17 —- Alan Gross lands on U.S. soil. President Obama announces that the U.S. will normalize relations with Cuba.

Photos: Alan Gross released from Cuba

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