Byzantine emperor Justinian II has his predecessors Leontios and Tiberios III publicly executed in the Hippodrome of Constantinople.

The Byzantine Empire, also known as the Eastern Roman Empire, was the continuation of the Roman Empire centred on Constantinople during late antiquity and the Middle Ages. Having survived the events that caused the fall of the Western Roman Empire in the 5th century AD, it endured until the fall of Constantinople to the Ottoman Empire in 1453. The term 'Byzantine Empire' was coined only after its demise; its citizens used the term 'Roman Empire' and called themselves 'Romans'.

Justinian II, nicknamed "the Slit-Nosed", was the last Byzantine emperor of the Heraclian dynasty, reigning from 685 to 695 and again from 705 to 711. Like his namesake, Justinian I, Justinian II was an ambitious and passionate ruler who was keen to restore the Roman Empire to its former glories. However, he responded brutally to any opposition to his will and lacked the finesse of his father, Constantine IV. Consequently, he generated enormous opposition to his reign, resulting in his deposition in 695 in a popular uprising. He only returned to the throne in 705 with the help of a Bulgarian army. His second reign was even more despotic than the first, and in 711 he was killed by mutinous soldiers.

Leontius was Byzantine emperor under the regnal name Leo from 695 to 698. Little is known of his early life, other than that he was born in Isauria in Asia Minor. He was given the title of patrikios, and made strategos of the Anatolic Theme under Emperor Constantine IV. He led forces against the Umayyads during the early years of Justinian II's reign, securing victory and forcing the Umayyad caliph, Abd al-Malik ibn Marwan, to sue for peace.

Tiberius III, born Apsimar, was Byzantine emperor from 698 to 705. Little is known about his early life, other than that he was a droungarios, a mid-level commander, who served in the Cibyrrhaeot Theme. In 696, Tiberius was part of an army sent by Byzantine Emperor Leontius to retake the North African city of Carthage, which had been captured by the Arab Umayyads. After seizing the city, this army was pushed back by Umayyad reinforcements and retreated to the island of Crete. As they feared the wrath of Leontius, some officers killed their commander, John the Patrician, and declared Tiberius the emperor. Tiberius swiftly gathered a fleet and sailed for Constantinople, where he then deposed Leontius. Tiberius did not attempt to retake Byzantine Africa from the Umayyads, but campaigned against them along the eastern border with some success. In 705, former emperor Justinian II, who had been deposed by Leontius, led an army of Slavs and Bulgars from the First Bulgarian Empire to Constantinople, and after entering the city secretly, deposed Tiberius. Tiberius fled to Bithynia, but was captured a few months later and beheaded by Justinian between August 705 and February 706. His body was initially thrown into the sea, but was later recovered and buried in a church on the island of Prote.