Didn’t the late great Godfather of Soul, James Brown, once quell a riot?
Yes, in a way. Following the murder of Martin Luther King, the broadcast of Brown's concert in Boston was made available for free to local residents, to keep them at home watching the concert instead of running in the streets. That cost the city of Boston $60K, but it worked. Also, Brown interceded when police tried to stop fans from storming the stage during the concert.
http://www.history.com/this-day-in-history/james-brown-calms-boston-following-the-king-assassination