The annual competition for the top holiday single in England has been dominated since 2004 by contestants for the television show “X-Factor” (think a British “American Idol”). It came as a surprise to everyone, Simon Cowell included, when this year’s award did not go to the favored pop star Joe McElderry but instead to Rage Against the Machine, whose song “Killing in the Name of” sold over 500,000 copies through album sales and online downloads. The victory was brought about by a true grass-roots movement through Facebook to oust the reality show’s hold on mainstream music in England. As a thank you, Rage Against the Machine pledged to play a free concert in London for a celebration. Six months later, they made good on their promise in front of 40,000 people.

The event took place at Finsbury Park in Northern London. The forecasted 70% chance of rain failed to deter anyone. First on stage was Gallows, a London-based band who draws their influences from British punk and American hardcore. They came close to stealing the show, putting on a phenomenal performance for their hometown crowd which included both a cover of “I Fought the Law” as well as the wall-of-death. Sick of it All would have been proud. The following act, London rapper Roots Manuva, was less compelling. While Rage has performed with a number of hip-hop artists in the past, Roots did not stack up to Cypress Hill or the Wu Tang. Finally, gypsy-rockers Gogol Bordello closed out the opening line up with a highly energetic set. Definitely do not pass up the chance to see this band, as you probably have not seen anything like them.

Finally, at 9pm, the black banner with the red star rose, and Rage Against the Machine took the stage. The band started their set with “Testify” and the full force of 40,000 fans was unleashed on the park. The crowd turned into a seething ocean of bodies that did not stop moving for the next 90 minutes. Rage laid out classics like “Bombtrack,” “People of the Sun,” “Know Your Enemy,” and “Bulls on Parade” before dedicating “Township Rebellion” to Palestine, calling for an end of the Israeli blockade.

They followed with “Bullet in the Head” and then brought out the organizers of the Facebook campaign that made the whole event possible. Tom Morello stated that “Fucking up the system never felt so good!” The band then paid tribute to the Clash by covering “White Riot,” which got the crowd moving even more, if possible. They closed their set with “Guerilla Radio,” “ Sleep Now in the Fire” and “Freedom.” After a short interlude, they came back for an encore performance of “Killing in the Name,” the clear crowd favorite for the night.

Given that some of these songs were written close to 20 years ago, it is clear that they are every bit as relevant now as ever. Their fantastic performance in Finsbury Park hammered this home, and showed just how much people can accomplish when they decide to fight the system.