Spring – A Muslim supply fleet of 760 ships under Sufyan arrives from
Egypt and
North Africa, concealing itself along the
Asiatic shore. The
Byzantines learn of the fleet's location from defecting
Christian Egyptian sailors. Emperor
Leo III sends the
Byzantine navy again; his
Greek fire ships destroy the enemy vessels in the
Sea of Marmara and seize their supplies on shore, denying the sieging army vital provisions.[1] On land the Byzantine troops ambush an advancing Arab army, and destroy it in the hills around
Sophon, south of
Nicomedia (modern
Turkey).[2][3][4][5] The Arab besiegers are still suffering from
hunger and pestilence.
August 15 –
Siege of Constantinople: A
Bulgar relief force attacks the
siege lines at
Constantinople, on the west side of the
Bosporus. Contemporary
chroniclers report that at least 22,000–32,000 Arabs are killed during the Bulgarian attacks. Caliph
Umar II is forced to lift the
siege after 13 months; the Muslim army attempts to withdraw back through
Anatolia, while the rest escapes by sea in the remaining vessels. The Arab fleet suffers further casualties to
storms, and an
eruption of the
volcano of
Thera.[6] According to Arab sources 150,000 Muslims perish during the campaign.[7]
King
Liutprand of the
Lombards builds a close
alliance with Charles Martel, and attacks the
Bavarian castles on the
River Adige, maintaining strategic control of the Alpine
passes in the Italian
Alps (approximate date).
Britain
King
Coenred of Northumbria dies after a 2-year reign. The throne is seized by
Osric, probably a younger brother, or half-brother, of the late king
Osred I.
^John Cairns, "Road to Manzikert" (2012). Byzantine Warfare in an Age of Crisis and Recovery (Chapter 3), p. 70.
ISBN978-1-84884-215-1
^Guilland, Rodolphe (1959). "L'Expedition de Maslama contre Constantinople (717–718)". Études byzantines (in French). Paris: Publications de la Faculté des Lettres et Sciences Humaines de Paris: 122.
OCLC603552986.
^Mango, Cyril; Scott, Roger (1997). The Chronicle of Theophanes Confessor. Byzantine and Near Eastern History, AD 284–813. Oxford: Oxford University Press. p. 546.
ISBN0-19-822568-7.