Even within Britain, grime has long been considered a niche genre. Pioneered by east London artist Wiley in the early 2000s, whose dark, stripped-down 140-beats-per-minute rhythms drew on U.K. garage and two-step influences and updated them, the sound then evolved on the rooftops of inner-city council estates as pirate radio prospered and MCs such as Dizzee Rascal and Crazy Titch literally battled to have their bars heard over the airwaves.