The assassination of Byzantine Emperor Nikephoros II Phokas marked a significant turning point in the history of the Byzantine Empire. Nikephoros II, who ruled from 963 until his assassination in 969, was a strong military leader known for his campaigns against Byzantium's enemies, including the Arabs and the Slavs. His reign, however, was also characterized by internal tensions, particularly with the aristocracy and nobility who often viewed his authoritarian governance unfavorably.

The emperor was married to Theophano, a woman of notable beauty and ambition. However, their marriage was fraught with difficulties, and Theophano was reportedly unhappy with Nikephoros’s military focus and harsh policies. She found herself involved with John I Tzimiskes, a prominent general and nobleman who had ambitions of his own in the Byzantine court. The conspiratorial couple plotted to eliminate Nikephoros II to pave the way for John’s ascension to the throne.

On December 11, 969, the coup was executed within the royal residence in Constantinople. Tzimiskes and some accomplices broke into the emperor's chamber, where they murdered him, effectively ending his reign. This assassination quickly led to the rise of John I Tzimiskes, who was proclaimed emperor shortly afterward, beginning a new regime that brought a slight shift in governance style. John's rule would see both continuity and change as he aimed to stabilize the empire while addressing the underlying issues that had plagued Nikephoros's reign.