Muhammad Ali (formerly known as Cassius Marcellus Clay Jr) passed away on 3 June at a hospital in Phoenix, Arizona after battling respiratory problems. He had been suffering from Parkinson's disease, which had grown more advanced in recent years, but the Olympic gold medallist continued to pack some powerful punches in the social arena, standing up against attacks on Muslims, supporting the black community and various other humanitarian issues.

IBTimes UK takes a look back at the life of the champion boxer through photos from some of his most memorable times.

Origins

Cassius Marcellus Clay Jr was born on 17 January 1942, in Louisville, Kentucky. He was one of five children to Cassius Marcellus Clay Sr and Odessa O'Grady. He took up boxing at the age of 12 under the guidance of Louisville police officer and boxing coach Joe E Martin.

Amateur wins and Olympic gold

As an amateur, he won six state and two national Golden Gloves titles, before going on to clinch the Light Heavyweight gold medal in the 1960 Summer Olympics in Rome. His amateur record was 100 wins with five losses.

Muhammad Ali
At the 1960 Rome Olympic Games, Cassius Clay, who won the gold medal in the light-heavyweight division, stands with silver medallist Zbigniew Pietrzykowski of Poland, and Giulio Saraudi (Italy) and Anthony Madigan (Australia), joint bronze.Getty Images
Muhammad Ali
A portrait of Muhammad Ali (then known as Cassius Clay) from the 1960sGetty Images

Start of his professional career

On 29 October 1960, Clay turned professional, winning his first 19 bouts – 15 of those by knockout. On 25 February 1964, aged just 22, he beat Sonny Liston, becoming the youngest boxer to take the title from a reigning heavyweight champion.

Muhammad Ali
25 February 1964: Cassius Clay celebrates his win over Sonny Liston in their heavyweight title fight at Miami Beach, Florida. Clay won the contest, becoming world champion for the first time, when Liston failed to come out at the start of the seventh roundGetty Images

He defended his title against former heavyweight champion Floyd Patterson on November 22, 1965 and famously stated before the bout: "I'm gonna put him flat on his back, so that he will start acting black."

Muhammad Ali
February 1964: Cassius Clay poses in the ring in mock victory over The Beatles, as they meet the press in New York during an American tourGetty Images

Conversion to Islam and the birth of Muhammad Ali

Shortly after becoming world champion, he converted to Islam and joined Nation of Islam, an American Muslim sect that advocated racial separation. He changed his name to Muhammad Ali, stating: "Cassius Clay is my slave name". He refused to serve in the US Army at a time when America was involved in the Vietnam War, and was stripped of his championship titles. Ali spent more than three years in exile, not allowed to fight between March 1967 and October 1970.

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Nation of Islam leader Elijah Muhammad addresses followers including Cassius ClayUS Library of Congress
Muhammad Ali
6 February 1967: World heavyweight boxing champion Muhammad Ali defends his title against Ernie Terrell, also gaining the WBA title. Shortly after this, Ali was stripped of his titles because he refused to be drafted to Army service, saying: "I got nothin' against them Vietcong."Getty Images
Muhammad Ali
A portrait of Muhammad Ali circa 1967. As a result of his refusing to join the Army to fight in Vietnam, he wasn't allowed to box competitively until late 1970US Library of Congress

Back to boxing

When the ban was finally lifted in 1970, he made his comeback with a fight against Jerry Quarry on 26 October. In December, Ali recaptured and defended the world championship in a bout with Oscar Bonavena at Madison Square Garden.

Muhammad Ali
2 November 1970: Muhammad Ali makes his eagerly-awaited comeback, beating fellow American Jerry Quarry in the third roundGetty Images

In 1971 his fight against Joe Frazier was considered one of the most famous bouts in history, being labelled The Fight of the Century.

Muhammad Ali
8 March 1971: In what was billed "The Fight of the Century", Joe Fazier knocks Ali to the canvas at Madison Square Garden. Ali lost by unanimous decision, his first professional defeat, and Frazier retained the titleAFP

In January 1974, Ali and Frazier exchanged punches in a non-title match that the former won by unanimous decision. In October 1974, Ali challenged undefeated world heavyweight champion George Foreman in a match that was nicknamed The Rumble in the Jungle. Ali knocked Foreman out by the end of the 8th round.

Muhammad Ali
30 October 1974: Muhammad Ali raises his arms after beating George Foreman in "the Rumble in the Jungle" in Kinshasa, Zaire. Ali knocked Foreman out in the eighth round, regaining the title of heavyweight boxing champion of the worldAFP

Muhammad Ali and Joe Frazier fought their last match Thrilla in Manila in 1975, which Ali won by technical knockout.

Muhammad Ali and Joe Frazier
The World Heavyweight title fight between Joe Frazier (left) and Muhammad Ali at Madison Square Garden 29 September 1975. Frazier won on points.Keystone/Getty Images
Muhammad Ali
15 September 1978: Muhammad Ali beats Leon Spinks to win the world heavyweight boxing title for the third time in his career, having lost it to Spinks seven months earlier. (Photo credit should read -/AFP/Getty Images)AFP

By the late seventies, Ali was seriously unwell, but insisted on continuing to fight. Three years after his final bout in 1981, it was announced he was suffering from Parkinson's syndrome. Ali's public appearances diminished over the years as he waged his long-running fight against the debilitating condition.

Muhammad Ali
7 October 1980: Muhammad Ali and Tom Jones have a mock sparring session. Ali's health had begun to deteriorate, and he was diagnosed as suffering from Parkinson's syndrome in 1984AFP

Muhammad Ali nicknamed himself "The Greatest" and is generally recognised as one of the best boxers of all time, retiring with a 56-5 record.

Personal life

Ali was married four times and had seven daughters and two sons. His daughter Laila Amaria from his third marriage to Veronica Porsche also took up boxing and went on to retire as an undefeated American professional boxer. In 1986, the retired boxer married Yolanda Williams, with whom he lived until his death.

He devoted himself to social causes, travelling the world on humanitarian missions, mingling with the masses and rubbing elbows with world leaders.

In 1990, Ali travelled to Iraq during the Gulf War and met with Saddam Hussein in an attempt to negotiate the release of American hostages.

Muhammad Ali
2 December 1990: Muhammad Ali is flanked by American hostages as they arrive at Amman airport from Baghdad. Ali was instrumental in the release of 15 US hostages held captive in Iraq during the Gulf WarAFP

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9 November 2005: US President George W Bush awards Muhammad Ali with the Presidential Medal of Freedom, as Ali's wife Lonnie watches, during a ceremony in the East Room of the White House in WashingtonReuters

Deteriorating health

In 2012, Ali was appointed as a titular bearer of the Olympic Flag during the opening ceremonies of the 2012 Summer Olympics in London. At the event, it was easy to recognise the toll his illness was having on him. He was unable to carry the flag into the stadium and had to be helped by his wife Yolanda (Lonnie).

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19 July 1996: Muhammad Ali holds up the torch prior to lighting a device that would carry the flame up the cauldron, during the opening ceremonies of the Olympic Games in AtlantaReuters
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Muhammad Ali is assisted as he walks behind the Olympic flag during the opening ceremony of the London 2012 GamesReuters
Lonnie and Muhammad Ali
Boxing legend Muhammad Ali and his wife Lonnie Ali ride a golf cart onto the field to represent the Louisville Cardinals for the coin toss against the Florida Gators prior to the start of the Allstate Sugar Bowl at Mercedes-Benz Superdome on 2 January 2013 in New OrleansKevin C Cox/Getty Images
Muhammad Ali
2 October 2013: Ali takes part in the US premiere of HBO's "Muhammad Ali's Greatest Fight" at Muhammad Ali Centre in Louisville, KentuckyGetty Images

On 20 December 2014, Ali was admitted to a hospital with a mild case of pneumonia and later again in January 2015, for a urinary tract infection.

On 2 June 2016 he was admitted to a Phoenix area hospital after suffering respiratory problems. He was moved on to life support and passed away on 3 June.

"After a 32-year battle with Parkinson's disease, Muhammad Ali has passed away at the age of 74. The three-time World Heavyweight Champion boxer died this evening," spokesman Bob Gunnell said in a statement. "The Ali family would like to thank everyone for their thoughts, prayers, and support and asks for privacy at this time."

“From the beginning, I was determined to be the best boxer.” #MuhammadAli

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Still the Heavyweight Champion of the World: Muhammad Ali! Today in 1965 #SonnyListon was stopped in one.

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“I’m gonna put him flat on his back.” #MuhammadAli

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“We become heroes when we stand up for what we believe in.” #MLKDay

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#Louisville Game Day! Go Cards!

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