Limardo Gascon became Venezuela's first gold medallist since 1968 and the world number 13 sparked jubilation among the South American nation's small contingent in the packed ExCeL arena after beating silver medallist Norway's Bartosz Piasecki 15-10.
'I've demonstrated that Venezuelans have got talent. I don't know what to say, I'm just speechless,' Limardo Gascon said.
Seth Kelsey had hoped to be the first male fencer ever to win Olympic gold for the USA but the world number 20 lost both his semi-final to Limardo and third-place contest in sudden death to the Republic of Korea's Jung Jinsun - the bronze medallist.
Venezuela have only ever won 12 medals of any colour in total. It is now two gold, two silver and eight bronze.
I've demonstrated that Venezuelans have got talent. I don't know what to say, I'm just speechlessRuben Limardo Gascon
Limardo Gascon, who put out world number five Max Heinzer in the last 16 and then Italy's reigning world champion Paolo Pizzo in the quarter-finals, raced into a 14-6 lead. He then lost the next four points, but finally made it.
'I came here to get a gold medal and I dedicate it to my country,' he added.
'My goal is to reach my dream, to be an Olympic champion, and that's what I set for myself when I was a child.'
In the women's Individual Sabre, Kim took gold after beating Russia's world champion Sofya Velikaya - the silver medallist. Olga Kharlan took bronze.
Earlier, Kim sprung a surprise by beating USA fighter Mariel Zagunis in the semi-final, who at one stage led 12-5.
Zagunis, her country's flag-bearer at last Friday's Opening Ceremony, was the champion in Athens and Beijing - indeed the only winner the recently-introduced event has had - and was on a 12-match unbeaten run.