Rage Against the Machine denies X-Factor winner No. 1 single
Rage Against the Machine's single, Killing In The Name, sold 500,000 downloads beating X Factor winner Joe McElderry's The Climb by 50,000 copies to clinch the top spot.
Their success followed a Facebook campaign designed to prevent another X Factor number one.
One retailer said it was a "truly remarkable outcome - possibly the greatest chart upset ever".
Speaking on the Radio 1 chart show, Zack de la Rocha from Rage said: "We are very, very ecstatic about being number one."
He added it was an "incredible organic grassroots campaign".
"It says more about the spontaneous action taken by young people throughout the UK to topple this very sterile pop monopoly," he said.
McElderry, 18, praised the campaign, adding: "It's been exciting to be part of a much-hyped battle and they definitely deserve congratulations."
The Los Angeles rock band's hit also set two records: it is the first single to reach the top of the charts on download sales alone and has achieved the biggest download sales total in a first week ever in the UK charts.