Possible Clues:

• Get your oar around the horse by way of protest
• Violence - difficulties
• Boorish, threatening behaviour (slang)
• Potential violence? In the past, old king intervened
• In slang, deliberate trouble-making
• A good attempt to suppress rioters' initial violent behaviour
• In the past, king imprisoned for trouble-making
• Violence - obstructiveness
• Troublemaking
• How a horse starts the trouble or comes back