Pope Constantine (; 6649 April 715) was the bishop of Rome from 25 March 708 to his death on 9 April 715. One of the last popes of the Byzantine Papacy, the defining moment of his pontificate was his 710/711 visit to Constantinople, where he compromised with Justinian II on the Trullan canons of the Quinisext Council. The city's next papal visit occurred in 1967.
Upbringing
Constantine was born in 664 in Tyre in the Umayyad Caliphate (now in Lebanon), and he was of Greek descent. Fluent in the Greek language, he immersed in Eastern rituals and practices. He was one of the papal legates to the Third Council of Constantinople in 680/681. Constantine became pope in March 708, less than two months later. Pope John VII had been sent the canons for approval and instead had sent them back, "without any emendations at all". The imperial mandate made it "obvious that the relentless emperor meant to settle once and for all the issue of Rome's acceptance of the Trullan decrees". Unlike his predecessors, Constantine neither delayed nor made excuses to avoid appearing in the imperial city; in fact, he "identified with Byzantium as perhaps no Roman pontiff before him ever had". Eleven of Constantine's thirteen companions who can be identified by name (two bishops, three priests, and all the ranking members of the papal chancellery and household) were also of Eastern extraction. Also accompanying Constantine was the future Pope Gregory II, then a deacon, and another Latin subdeacon Julian. Justinian II was in Nicaea at the time and urged the pontiff to meet him in Nicomedia.
Rejection of monothelitism
thumb|right|Constantine refused to accept coins minted with the image of [[Philippicus.]]
Justinian II was killed by his mutinous troops in November 711, shortly after Constantine's return to Rome. The new emperor, Philippicus, was an adherent of monothelitism, and rejected the arrangements of the Third Council of Constantinople. He demanded Constantine's support of the view that Christ had only one will. In 712, Constantine rejected Philippicus' demand to revive monothelitism. He further refused to receive an imperial portrait or coins with the emperor's image and also refused to commemorate the emperor in Mass.