The deeply divisive political figure, who led a rebel army to improbable victory on the island nation and embraced Soviet-style communism, defied the power of 10 US presidents and snubbed an eleventh, Barack Obama, when he visited the country in March.
The revolutionary communist is the longest-ever-serving head of state, aside from monarchs, having controlled the island nation from 1959 until 2006, and remained nominally in charge until 2008. News of his death was met with celebration in Miami, Florida, where many Cuban-Americans live in exile, and solemnity inside his country, where he remains an icon, if a controversial one.
In 2006, after he almost died of a medical condition and had to hand over power to his younger brother Raúl Castro, he vowed to live long enough to see then US Head of State George Bush junior out of office. He did that, and survived almost to the end of Barack Obama's two successive terms as president.
Throughout his unprecedentedly lengthy reign, he was a thorn in the side of the United States administration antagonising president after president, and surviving dozens of attempts to assassinate or overthrow him, launched as result of his outright defiance of US hegemony.
But despite the fact he has posed a similar problem for all of them, there has been little consistency in how different US leaders have approached the rebel president.
Dwight D. Eisenhower, 1953-1961: Initial ally, who quickly regretted helping Castro win power and severed all ties
In March 1958, the Eisenhower administration suspended arms shipments to the incumbent Cuban dictator Fulgencio Batista, which helped a young Fidel Castro lead his rebel army to victory. Initially, the United States welcomed Castro to power, but concerns about Castro's left-wing politics and intentions as president led Mr Eisenhower to snub Castro when he visited Washington in April 1959. Castro instead met with then Vice President Richard Nixon.
In May 1960, Cuba and the Soviet Union resumed diplomatic relations, and Cuba began importing Soviet oil. American-owned refineries in Cuba refused to refine the oil, so Castro confiscated the facilities.
In response to the seizing of oil refineries and other US properties in Cuba, in addition to Castro's growing friendship with US sworn-enemy the Soviet Union, the United States placed a partial economic embargo on Cuba in October 1960 that was expanded in October 1962 to cover all trade between the two countries.
Just before Eisenhower left office in January 1961, the US government broke all diplomatic relations with Havana, setting the tone for much of the next five decades.
John F. Kennedy, 1961-1963: Helped Cuban exiles launch unsuccessful Bay of Pigs invasion, failed, promised the Soviets he would not try again, had the CIA intensify efforts to assassinate Castro instead
John F. Kennedy oversaw the most volatile period in the two countries' relationship.
In April 1961, Cuban exiles supported by the United States government invaded Cuba at the Bay of Pigs. The mission was planned by Mr Eisenhower's administration but executed on Mr Kennedy's orders, in the belief that the Cuban people would rise up against Castro and aid the US-backed invasion. When they did not, the mission ended in disaster, with many fighters captured of killed by the Cuban army.
In October 1962, US planes photographed Soviet missile-construction sites in Cuba, triggering a panic, known as the Cuban Missile Crisis.
Eventually the Soviet government agreed to remove the missiles, on the condition that Mr Kennedy promised the United States would not invade Cuba again.
Mr Kennedy kept his word, but covert missions to overthrow Castro continued, with the Kennedy administration allegedly placing intense pressure on the CIA to “get rid of Castro”. Between 1961 and 1965 there were at least eight serious attempts to kill the communist leader.
One of the most famous assassination attempt was made by Castro's ex-lover Marita Lorenz, who allegedly agreed to help the CIA and attempted to smuggle a jar of cold cream containing poison pills into his room. When Castro learned about her intentions, he reportedly gave her a gun and told her to kill him but her nerve failed.
Under Mr Kennedy, the CIA also knowingly worked with two of America's most-wanted Mafia figures in an attempt to have Castro killed.
Some plots did not aim to kill Castro, perhaps due to how difficult that proved to be, but to destroy his character instead, for example CIA documents have revealed that at one point they planned to use thallium salts, a poison historically used to kill rats which has a depilatory effect, to destroy Castro's famous beard, demonstrating his weakness and vulnerability to the nation.
Another absurd idea recorded in official documents involved lacing a radio studio with an LSD like substance, which would cause Castro get high during a live broadcast and damage his public image.
In February 1963, the Kennedy administration prohibited Americans from travelling to Cuba and from making financial transactions with the country.
Lyndon B. Johnson, 1963-1969: Continued trying to kill Castro, opened the door to Cubans fleeing his regime, but then got distracted by the Vietnam war
Mr Johnson continued to support covert operations aimed at overthrowing or killing Castro, but he abided by Mr Kennedy's promise not to attempt another invasion.
In November 1966, the Johnson administration passed the Cuban Adjustment Act, giving 123,000 Cubans who had fled the Castro regime permission to apply for permanent residence in the United States if they had been in the country for two years.
By the end of the Johnson administration, the US government had shifted its attention from Cuba to the war in Vietnam.
Richard Nixon, 1969-1974: Stepped up attempts to overthrow Castro before officially agreeing to stop, and focusing instead on Vietnam
Richard Nixon appeared relatively uninterested in Castro, because his focus was instead on the Vietnam war.
But, as a firm supporter of Mr Kennedy in the 1961 Bay of Pigs Invasion and 1962 Cuban Missile Crisis, behind the scenes he initially stepped up covert operations targetting Castro.
He maintained close relations with the Cuban-American exile community through his close friend, Bebe Rebozo, a Florida banker and businessman originally from Cuba, who allegedly often suggested ways to “irritate” Castro.
In August 1970, concerned Mr Nixon might attack Cuba despite Mr Kennedy's promise, the Soviets asked Mr Nixon to reaffirm the agreement. Despite his hard line against Castro, Mr Nixon agreed. He officially ended all US attempts to overthrow Castro, and did not develop any major US-Cuba policy initiatives during his presidency.
Gerald Ford, 1974-1977: Attempted to normalise relations with Cuba, but severely fell out with Castro over his support of communist parties and revolutions in other countries, considered air strikes
Mr Ford was the first president to attempt to normalise relations with Cuba, but the initiative ended in December 1975 when Castro sent troops to southern Africa to support the Marxist regime in Angola. Castro also angered the Ford administration by supporting the Puerto Rico independence movement.
In 1976, Secretary of State Henry Kissinger considered deploying air strikes against Cuba in response to Castro's support for the Angolan regime, according to now declassified official files.
“I think we are going to have to smash [Cuban President Fidel] Castro,” Mr Kissinger told Mr Ford in a meeting. “We probably can't do it before the [1976 presidential] elections.”
“I agree,” the president responded.
Jimmy Carter, 1977-1981: Tried again to fix relations, failed, but arguably laid the groundwork for future reconciliation, accepted an exodus of refugees from Cuba
Mr Carter made the second serious effort to reach out to Castro and normalise US-Cuba relations. Initially he had some success, and the two presidents agreed to open downgraded embassies called “Interest Sections” in Havana and Washington. Mr Carter also removed all travel restrictions in order to allow Americans to visit Cuba.
These efforts were again derailed by Cuba sending troops to Africa, this time to Ethiopia in support of the Soviet-backed government there.
In April 1980, refugees began a mass exodus from the Cuban port of Mariel to the United States after Castro announced that Cubans who wished to leave the island would be permitted to do so. Many of the 125,000 refugees eventually settled in Florida.
When Mr Carter left office, the Interest Sections remained, and some people attribute improved relations between the two countries decades later in part to Mr Carter's work.
In 2002—well after leaving office in 1981—Mr Carter traveled to Cuba at the invitation of Castro, becoming the first US president, in or out of office, to do so after the 1959 revolution.
Mr Carter reportedly sought to improve understanding between the two peoples and the two governments, and made a speech in Spanish, broadcast live to the entire island, in which he called on the US as the more powerful country to take the first step and lift the embargo. He also called on the Cuban government to respect its own constitution by protecting free speech and assembly, and allowing citizens to petition for a change in the laws.
Afterwards, Castro invited Mr Carter to watch a baseball game, and reportedly did not comment on Mr Carter's challenging speech. At the baseball game, Castro asked Mr Carter to walk out to the pitcher’s mound to throw out the first pitch without his security detail, to demonstrate Mr Carter’s confidence in the Cuban people. Mr Carter did as Castro asked, in a major gesture of trust.
Ronald Reagan, 1981-1989: Sent troops to Grenada to fight Cuban forces building an airport, re-established travel ban and tightened trade restrictions
The Reagan administration is considered to have been the most hostile to Cuba since the Bay of Pigs invasion, and reversed most of the progress Mr Carter made.
During Mr Reagan's presidency, the US government discovered that Cuban forces were building an airstrip in Grenada which they believed could be used for military aircrafts.
This discovery, coupled with a coup by allegedly pro-Soviet elements in Grenada, prompted Mr Reagan to send US troops to the island in October 1983. The Grenada intervention is the only time that US and Cuban troops have engaged in combat with each other.
The Reagan administration also cited Cuban support for rebel forces in El Salvador and for the Sandinista government in Nicaragua as justifying US involvement in Central American conflicts.
Under Reagan, the US government re-established the travel ban and prohibited US citizens from spending money in Cuba.
George H. W. Bush, 1989-1993: Tightened the trade embargo even more, despite the fact Soviet subsidy termination left Cuba broke
The Soviet bloc collapsed, leaving Cuba no longer serving as a Soviet satellite in the Western Hemisphere. In December 1991, Soviet subsidies to Cuba, worth $6 billion annually, were terminated.
Cuba was no longer considered a serious security threat to the United States, but despite this the Bush administration tightened the trade embargo in an effort to squeeze the Castro regime and hasten its demise.
In October 1992, Congress prohibited foreign subsidiaries of US companies from trading with Cuba, travel to Cuba by US citizens, and family remittances to Cuba.
Bill Clinton, 1993-2001: Sought to normalise relations with Cuba, again, failed, again, panicked about refugees
After Castro declared an open migration policy in August 1994, 30,000 refugees left Cuba for the United States. Mr Clinton considered the refugee outflow as threatening to US interests, and the US Coast Guard was ordered to intervene to prevent further migration.
In October 1995, Bill Clinton became the third president to attempt to improve relations with Cuba. The effort ended in February 1996, when Cuban missiles shot down two civilian, US registered aircraft in international airspace. Three Americans and one Cuban legal resident were killed.
In March 1996, Congress passed the Helms-Burton Act, codifying the embargo against Cuba into law. The Clinton administration attempted to bypass Castro by promoting “people-to-people” contacts.
Towards the end of Mr Clinton's second term, tensions with Cuba spiked when a young Cuban boy, Elian Gonzalez, was rescued from the Florida Straits clinging to a rubber ring. After he was placed with maternal family members in Miami - his mother had drowned in their attempt to reach America - courts in the US determined in 2000 that the boy should be returned to his father in Cuba to the fury of the Cuban-American community.
George W. Bush, 2001-2009: Tightened trade embargos, placed new restrictions on travel, and limited money transfers from Cuban-Americans to relatives
President Bush junior ordered a further tightening of the trade embargo, with new restrictions on travel to Cuba and limitations on the transfer of money from Cuban-Americans to their relatives on the island.
In 2002, some Bush administration officials claimed that Cuba was engaged in research and development on an offensive biological warfare program.
President Bush announced a programme to assist the transition to a democratic Cuba once Castro and his brother Raúl were both removed from power.
The Castropedia: Fidel's Cuba in facts and figures
The Castropedia: Fidel's Cuba in facts and figures
Attempts made on Castro's life since he came to power in 1959: 638 (according to Fabian Escalante, former Cuban security chief)
Castro is a baseball fan - with 16 teams making up the Cuban National Baseball League
Size of the original rebel army led by Castro and including Che Guevara that sailed to Cuba in 1956, eventually toppling President Batista on 1 January 1959: 82
Acts of "civil disobedience" logged in Cuba in 2005, according to a report by the exiled Cuban Democratic Directorate: 3,322
Miguel Vinas/AFP/Getty Images
Age at which Castro began smoking cigars: 15 Age at which Castro gave up smoking cigars: 59
Jorge Rey/Getty Images
Jorge Rey/Getty Images
Total number of Cubans believed to have emigrated while Castro was in power: about 1.4 million (81 per cent of whom have settled in North America)
Rodrigo Arangua/AFP/Getty Images
Duration of a speech Castro made at the UN in 1960: 4 hours 29 minutes (listed by the Guinness Book of Records as the longest speech made in the United Nations)
Tom Mihalek/Getty Images
Films: Castro is listed as an "uncredited extra" in the 1946 musical Holiday in Mexico and as a "poolside spectator" in the romantic comedy Easy to Wed (also 1946)
Hrvoje Polan/AFP/Getty Images
And after Castro had handed over power to his brother...
Barack Obama, 2009-present:
The United States restored diplomatic relations with Cuba on July 20, 2015, but has maintained the commercial, economic and financial embargo against the communist island.
President Barack Obama, however, has moved to also restore economic relations with the country, implementing a number of changes as recently as October.
The changes included the easing of restrictions on the island in an attempt to create more economic opportunities between the two countries. The administration approved a package of regulatory changes that was intended to expand scientific, humanitarian, trade and commercial opportunities between the US and Cuba.
However when Mr Obama visited the country in March 2016, he did not meet with Castro, who retired in 2008, nor mention him at all in any of the speeches he gave.
After his visit, Castro snubbed Mr Obama, accusing the US leader of “sweet-talking the Cuban people” and ignoring the accomplishments of Communist rule, in an opinion piece carried by all state-run media.
“One assumes that every one of us ran the risk of a heart attack listening to these words,” Castro said in his column, dismissing Obama's comments as “honey-coated” and reminding Cubans of the many United State's efforts to overthrow and weaken the Communist government.
“We don't need the empire to give us any presents,” he wrote.