A chariot-racing feud nearly toppled an emperor and burned a capital

In 532 AD, two rival chariot-racing factions in Constantinople, the Blues and the Greens, united in anger over taxes and turned on Emperor Justinian I. Rioters burned much of the city, including the original Hagia Sophia, and nearly forced Justinian to flee by ship. His general Belisarius crushed the revolt inside the Hippodrome, killing an estimated 30,000 people in a single day.

— William Rosen, Justinian's Flea: Plague, Empire, and the Birth of Europe — 2007
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