Caliph Mu'awiya I, who had emerged in 661 as the ruler of the Muslim Arab empire following a civil war, renewed aggressive warfare against Byzantium after a lapse of some years and hoped to deliver a lethal blow by capturing the Byzantine capital of Constantinople.

Finally the Byzantines, under Emperor Constantine IV, destroyed the Arab navy using a new invention, the liquid incendiary substance known as Greek fire.

A peace treaty was signed soon after, and following the outbreak of another Muslim civil war, the Byzantines even experienced a brief period of ascendancy over the Caliphate.

The siege left several traces in the legends of the nascent Muslim world, although it is conflated with accounts of another expedition against the city in 669, led by Mu'awiya's son, the future ruler Yazid.

Following the disastrous Battle of the Yarmuk in 636, the Byzantine Empire withdrew the bulk of its remaining forces from the Levant into Asia Minor, which was shielded from the Muslim expansion by the Taurus Mountains.

Muslim raids against the Cilician frontier zone and deep into Asia Minor began as early as 640, and continued under Mu'awiya, then governor of the Levant.

[5][6][7] Mu'awiya also spearheaded the development of a Muslim navy, which within a few years grew sufficiently strong to occupy Cyprus and raid as far as Kos, Rhodes and Crete in the Aegean Sea.

[11] The peace lasted until the end of the Muslim civil war in 661, from which Mu'awiya and his clan emerged victorious, establishing the Umayyad Caliphate.

The Arab troops under Fadala ibn Ubayd arrived too late to assist Saborios, who had died after falling from his horse, and they spent the winter in the Hexapolis around Melitene awaiting reinforcements.

[17][16] In early 669, after receiving additional troops, Fadala entered Asia Minor and advanced as far as Chalcedon, on the Asian shore of the Bosporus across from the Byzantine capital, Constantinople.

The Byzantine chronicler Theophanes the Confessor reports that the Arabs remained before Chalcedon for a while before returning to Syria, and that on their way they captured and garrisoned Amorium.

Its garrison of 12,000 men was regularly rotated back to Syria, a small fleet was attached to it for defence and raiding, and the Arabs even sowed wheat and brought along animals to graze on the island.

According to the account of Theophanes, they landed on the Thracian shore near Hebdomon in April, and until September were engaged in constant clashes with the Byzantine troops.

As the Byzantine chronicler reports, "Every day there was a military engagement from morning until evening, between the outworks of the Golden Gate and the Kyklobion, with thrust and counter-thrust".

[1] The subsequent peace also gave a much-needed respite from constant raiding to Asia Minor and allowed the Byzantine state to recover its balance and consolidate itself after the cataclysmic changes of the previous decades.

[41] The failure of the Arabs before Constantinople coincided with the increased activity of the Mardaites, a Christian group living in the mountains of Syria that resisted Muslim control and raided the lowlands.

They were drawn out until 679, which gave the Arabs time for a last raid into Asia Minor under 'Amr ibn Murra, perhaps intended to put pressure on the Byzantines.

The Caliphate's division during the Second Muslim Civil War allowed Byzantium to achieve not only peace but also a position of predominance on its eastern frontier.

[53][54] The most prominent among them in later tradition is Abu Ayyub al-Ansari, one of the early companions (Anṣār) and standard-bearer of Muhammad, who died of illness before the city walls during the siege and was buried there.

[58] They record that the large, well-fortified capital city of Fu lin (拂菻, i.e. Byzantium) was besieged by the Da shi (大食, i.e. the Umayyad Arabs) and their commander "Mo-yi" (Chinese: 摩拽伐之, Pinyin: Mó zhuāi fá zhī), who Friedrich Hirth has identified as Mu'awiya.

[62][63][64] Constantin Zuckerman believes that an obscure passage in Cosmas of Jerusalem's commentary on Gregory of Nazianzus, written in the early eighth century, must refer to the Arab blockade of Constantinople.

According to Howard-Johnston, "The blockade of Constantinople in the 670s is a myth which has been allowed to mask the very real success achieved by the Byzantines in the last decade of Mu'awiya's caliphate, first by sea off Lycia and then on land, through an insurgency which, before long, aroused deep anxiety among the Arabs, conscious as they were that they had merely coated the Middle East with their power".