Driven by her desire for Olympic glory, the 17-year-old switched to represent her father's country Algeria.
"I had put the Olympic medal as my screen saver on my phone. I think I'll change it to put the real one," said a smiling Nemour after her daring high-flying acrobatic routine brushed aside her rivals at Bercy Arena to claim a first gymnastics medal for Africa.
Her score of 15.700 pushed China's Qiu Qiyuan, who had taken the world title ahead of her last year, into the silver medal position, with American Sunisa Lee snatching bronze.
Gymnastics great Simone Biles did not make it past qualifying on the apparatus a week ago in which Nemour lead the way.
As Nemour soared in Paris, the French gymnastics team slumped at their home Olympics with none of the women's competitors qualifying for the apparatus finals.
On Sunday, France's only remaining gymnastics hope in the Paris Olympics, Samir Ait Said, failed to medal in the men's rings final.
"It was complicated for them," said Nemour. "I'm obviously sad for them because I worked alongside the girls of the French team, but that's competition."
It has been a long road for Nemour.
Born in Indre-en-Loire, in central France, she discovered gymnastics at a young age and was quickly spotted by French coaching couple Marc and Gina Chirilcenco.
But three years ago, a growth spurt of 14 centimetres (5.5 inches) in a year just after she turned 13 caused a bone problem which required surgery on both knees.
Nemour was waiting for the green light to resume competitions but the French federation insisted on a very gradual resumption.
A standoff developed and Nemour was excluded from the France team.
"Clearly, I was angry, sad, I didn't understand, I thought it wasn't fair," Nemour told AFP.
"But my coach says that when you can't go this way, you take another route and there will always be another way.
"I'm delighted to have won this medal for Algeria. It's the first medal for Africa and I'm proud to have won this medal for them."
Nemour finished fifth in the all-around in Paris earlier this week.
Former Olympic all-around champion Lee was amazed by Nemour's performance in Paris.
"It was incredible," said Lee. "Watching her on bars is like watching a feather. She's flying. It's so light. It just looks so good and it's so fast and so smooth."
