The Nika riots (), Nika revolt or Nika sedition took place against Byzantine Emperor Justinian I in Constantinople over the course of a week in 532 AD. They are often regarded as the most violent riots in the city's history, with nearly half of Constantinople being burned or destroyed and tens of thousands of people killed. Background The ancient Roman and Byzantine empires had well-developed associations, known as demes, which supported the different factions (or teams) to which competitors in certain sporting events belonged, especially in chariot racing. There were initially four major factions in chariot racing, differentiated by the colour of the uniform in which they competed; the colours were also worn by their supporters. These were the Blues (Veneti), the Greens (Prasini), the Reds (Russati), and the Whites (Albati), although by the 6th century the only teams with any influence were the Blues and Greens. Emperor Justinian I was a supporter of the Blues. The demes had become a focus for various social and political issues for which the general Byzantine population lacked other forms of outlet. They combined aspects of street gangs and political parties, taking positions on current issues, including theological problems and claimants to the throne. They frequently tried to affect imperial policy by shouting political demands between races. The imperial forces and guards in the city could not keep order without the cooperation of the factions, which were in turn backed by the aristocratic families of the city; these included some families who believed they had a more rightful claim to the throne than Justinian. In 531 some members of the Blues and Greens were arrested for murder in connection with deaths during rioting after a chariot race. Relatively limited riots were not unknown at chariot races, similar to the football hooliganism that occasionally erupts after association football matches in modern times. The murderers were to be executed, and most of them were. However, on January 10, 532, two of them, a Blue and a Green, escaped and sought sanctuary in a church surrounded by an angry mob. Justinian was nervous: he was in the midst of negotiating with the Persians over peace in the east at the end of the Iberian War, and now he faced a potential crisis in his city. Therefore, he declared that a chariot race would be held on January 13 and commuted the sentences to imprisonment. The Blues