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.

The Roman Empire had well-developed associations, known as demes,[2] which supported the different factions (or teams) to which competitors in certain sporting events belonged, especially in chariot racing.

[4] What's more, Justinian's previous ardent support of the Blues made him seem biased and contributed to his waning control of the capital leading up to 532.

[7] In 531 AD some members of the Blues and Greens were arrested by the city prefect Eudaimon for murder in connection with deaths during rioting after a chariot race.

Hearing this, monks from the monastery of St Conon took the two partisans across to the church of St. Laurence, where they were put under surveillance by the prefect's troops.

[10] 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.

This was perceived by the Greens as an oppressive action akin to the reforms implemented in the civil service, while the Blues felt a sense of betrayal.

[15] As a result, the successful implementation of significant legal reforms by an emperor was viewed as lending legitimacy to their reign, while a lack of progress in this area was interpreted as a sign of divine displeasure.

While initial Byzantine victories at Dara in the spring of 530 and Satala in the summer of 530 had temporarily enhanced his legitimacy, the defeat at Callinicum in 531 and the deteriorating strategic situation had a detrimental effect on the emperor's reputation.

[15] The legal reforms were met with resistance from the aristocracy from their inception, as they eliminated the ability to utilize obscure laws and jurisprudence to evade unfavorable judgments.

Furthermore, the fact that activity towards the factions had largely been unrestricted for three decades prior during Justin's reign, meant the likelihood of them working together in common cause was far greater.

By the end of the day, at race 22, the partisan chants had changed from "Blue" or "Green" to a unified Nίκα ("Nika", meaning "Win!

It is believed that on January 14, the second day of the riots, Justinian, rather than negotiating political concessions, offered to host more races and games in an attempt to appease the rioters.

[27] Although, he later granted titles and land to Hypatius' and Pompeius' children,[28] and some of the officials Justinian dismissed in response to the demands of the rioters, like John the Cappadocian were reinstated to their prior positions.

Indeed, in 565, in the last year of Justinian's reign, fighting became so bad again that the city prefect Julian had to purge the factions to restore peace.

Geoffrey Greatrex offers the most common view that Justinian's miscommunication, indecisiveness and inconsistency with the circus factions caused and escalated the riots.

[5] It is the view of Mischa Meier that Justinian may have intentionally provoked the riots so that his political rivals within the senate, like Hypatius may reveal themselves to him.

[b][19] The motive for departure, whether it happened or not, is contested; Theophanes believes it was due to panic, whereas Westbrook suggests Justinian hoped to get fresh troops garrisoned in Thrace.

[18] Procopius provides an insider perspective from the palace while Malalas recounts the Nika riots as an outsider of the events in the city.