The Jamaican’s flawless display in a scorching 10.61 seconds was enough to upset compatriots Shelly-Ann Fraser-Pryce and Shericka Jackson, who took silver and bronze respectively.
But the 29-year-old has suffered from injuries between her triumph at Rio 2016 and the Games this summer, picking up an Achilles tendon injury at the 2019 World Championships in Doha.
But Thompson-Herah persevered and overcame the pre-Games favourite Fraser-Pryce.
Thompson-Herah told BBC Sport trackside after her stunning performance: "God is amazing, I've been struggling, I see all the bad comments, I see everything, for me to stay focused and keep my composure.
“I use them as my motivation, to take me here today, more than enough. I felt it, I'm so excited to celebrate early, I'm grateful. I'm lost for words right now, that is amazing."
While silver medalist Fraser-Pryce added: “It wasn’t the best 30m because I had a stumble at about the third step and I never recovered from it. Nevertheless I am grateful to be able to come out here and represent what God has given me.Article Reactions
“I am excited because as a mother and my fourth Olympics to be able to stand again on the podium is just a tremendous honour. I am hoping wherever in the world, mothers, athletes, females we understand that there is so much more we can achieve.
“It is crazy, but you know my emotions are still very raw right now. I am sure I will go home and there will be some tears. I have been through this many, many times, so I am just really excited about what I have been able to do tonight.”
While former Olympic champion Michael Johnson admitted the start from the reigning champion caught him off guard: “I was surprised because Elaine Thompson-Herah got an amazing start, she executed that race to perfection.
“Shelly-Ann Fraser-Pryce always has a good start but Elaine was with her the whole way. Shelly-Ann then had to make a decision, and she made the wrong one, which most likely tightened her up. Elaine just gained confidence throughout the race.”
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