The May 19, 1962, fundraiser at New York City’s Madison Square Garden was billed as a 45th birthday celebration for President John F. Kennedy, even though his actual birthday was 10 days later. The White House, looking to erase Democratic Party debt incurred during the 1960 election, invited a number of celebrities to participate, including Marilyn Monroe, who was in Hollywood filming Something’s Got to Give.

Monroe traveled to New York against the wishes of her bosses at 20th Century Fox, who later fired her from the project. “Marilyn had already missed quite a bit of time on the set because of her illnesses,” explained Scott Fortner, a historian of the actress who has one of the world’s largest collections of Marilyn Monroe-owned memorabilia. Though she was eventually re-hired, her untimely death on August 5, 1962, prevented the movie from ever being completed.

Marilyn Monroe sings “Happy Birthday” to Kennedy on May 19, 1962. (Credit: Yale Joel/Life Magazine/Time & Life Pictures/Getty Images)

Throughout her career, Monroe was known for constantly arriving late. So at the birthday gala, master of ceremonies Peter Lawford—a Rat Pack member and JFK’s brother-in-law—performed a running gag in which he continually introduced her, only to see no one come onstage. 

Finally, at the end of the evening, Monroe slithered out in an open-backed dress made of flesh-colored soufflé gauze encrusted with rhinestones. The gown was so tight that she reportedly had to be sewn into it. “Mr. President, the late Marilyn Monroe,” Lawford announced, referring yet again to the star’s habitual tardiness. As the audience cheered, Monroe closed her eyes and began to sing in a sultry voice:

Happy birthday to you
Happy birthday to you
Happy birthday, Mr. President
Happy birthday to you

Thanks, Mr. President,
For all the things you’ve done,
The battles that you’ve won
The way you deal with U.S. Steel
And our problems by the ton
We thank you so much
Everybody, happy birthday

A giant cake was then brought out, and Kennedy took the stage. He thanked all of the celebrities who had performed, including Ella Fitzgerald, Maria Callas, Jack Benny, Peggy Lee and especially Monroe. “I can now retire from politics after having had ‘Happy Birthday’ sung to me in such a sweet, wholesome way,” Kennedy joked.

Monroe’s performance only lasted about a minute. But it caused an immediate sensation, in part because of rumors that she and the president were having an affair. One columnist wrote that the actress seemed to be “making love to the president in direct view of 40 million Americans.” Actress Joan Copeland, who attended the gala, said Monroe sounded breathy because she was anxious and winded from running around backstage. According to Fortner, however, “She knew exactly the way she wanted to sing it. She rehearsed it well in advance. It wasn’t an accident.”

The event turned out to be one of Monroe’s final public appearances—and, JFK biographer Michael O’Brien observed, the last time she saw the president. That August, she died at age 36 of an apparent drug overdose, and the following year Kennedy was assassinated in Dallas. Yet the aura surrounding them lives on, with Monroe’s dress selling for nearly $1.3 million at a 1999 auction. 

“You have the greatest sex symbol of her day singing ‘Happy Birthday’ to President Kennedy,” Fortner said. “It was just one of those moments in time that can never be repeated.”

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