Marks, 22, just missed out on bronze in Tokyo 2020, but won the women’s title in Tahiti.
The surfing competition was staged 9,800 miles from Paris, in waters off the French Polynesian island where Vaast was born and raised.
Tahiti was picked for the famed Teahupo’o wave, which Vaast, 22, first rode at the age of eight.
He got off to a good start in the final, riding a near-perfect 9.5, before Australia’s Jack Robinson responded with a 7.83.
Vaast’s next wave gave him a total of 17.67, and Robinson was unable to register another ride, allowing Vaast to become Tahiti’s first Olympic winner.
We were lucky since we only had three waves to surf before the ocean flattened out,” Vaast added.
He believed there was a mystical energy unique to the location that drove him to the gold medal.
“We have a good relationship [with the surf], we call it the ‘mana’, and in this contest I felt it the whole time,” stated Vaast.
“[I’m] proud to say that surfing originated in Polynesia; this means a lot to me. The wish has come true. “I hope this serves as an inspiration to Tahiti’s youth.”
Vaast defeated Peru’s Alonso Correa in the semi-finals, while Robinson upset Brazil’s Gabriel Medina.