Martin Luther King Jr
Civil rights leader Martin Luther King Jr. is pictured with his wife, Coretta Scott King, Dec. 9, 1964. Getty Images

Martin Luther King Jr. is celebrated as a civil rights leader and humanitarian, but he wasn’t perfect. When it came to his personal life, King was a serial cheater. To find out more lesser-known facts about the civil rights leader, continue reading:

King committed adultery again and again: Ava DuVernay's Oscar-nominated biopic “Selma” depicts King as being unfaithful to his wife, Coretta Scott King. Though the reasons this information is public knowledge isn't ethical -- the FBI wanted to use it to discredit King -- he cheated on Coretta so many times that she was reportedly disillusioned with their marriage.

The FBI recorded one of his trysts at a Washington, D.C., hotel and sent the audiotape to his wife. His last night alive wasn’t with the woman he married -- it was with someone else. When he was assassinated at the Lorraine Motel in Memphis, the young woman was asked to stay out of the ambulance so King’s reputation would not be tainted.

King had a “weakness for women,” Ralph Abernathy wrote in his 1989 autobiography. This was a known fact among his staff. They “all understood and believed in the biblical prohibition against sex outside marriage. It was just that he had a particularly difficult time with that temptation.”

DuVernay found herself in hot water when her film suggested it was President Lyndon Johnson who sent proof of King’s womanizing to Coretta, which is something Johnson loyalists deny, the Hollywood Reporter wrote. The insinuation was left out of the original screenplay, but DuVernay wrote it in. In truth, it was FBI Director J. Edgar Hoover who ordered King to be bugged.

His real name wasn’t Martin Luther: Martin Luther King Jr. was born Michael King Jr. Jan. 15, 1929. His name was changed to Martin Luther after his father traveled to Germany and became inspired by the Protestant Reformation leader Martin Luther. His father, Michael Sr., changed his own name and the name of his 5-year-old son, History.com wrote. The civil rights leader never legally changed it though.

King had a bad heart, anatomically: When the 39-year-old King died he had the heart of a 60-year-old man, autopsy results showed. Part of the reason was poor eating habits. His aides reportedly had to monitor his diet to make sure his weight didn’t balloon.

He was a Republican, conservative politicians claim: There isn’t much evidence to back this up, especially since King’s son refuted the claim, but King’s niece, the Rev. Alveda King, said in a 2009 interview that she thought her uncle was a registered GOP voter. In recent times, the Republican Party has tried to capitalize on this.

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