Siege of Constantinople (717-718)
The Siege of Constantinople (717-718) was a significant military confrontation between the Byzantine Empire and Arab forces led by General Maslamah ibn ʿAbd al-Malik. Initiated on August 15, 717, the siege involved a massive force of approximately 80,000 troops and a fleet of 1,800 ships aiming to capture the strategically vital city, which was protected by formidable walls and water barriers. Despite being heavily outnumbered, the Byzantine defenders, led by Emperor Leo III, were bolstered by a strong belief in divine protection. A crucial turning point occurred when Leo III employed Greek fire to decisively disrupt the Arab fleet, resulting in the destruction and capture of numerous ships.
The harsh winter conditions further weakened the besieging forces, causing significant casualties. By spring, a series of strategic maneuvers and the defection of Arab soldiers allowed the Byzantines to launch a counter-offensive. Ultimately, the siege ended with the withdrawal of the Arab forces on August 15, 718, marking a pivotal moment in history. This successful defense is often regarded as a critical event that helped preserve the Byzantine Empire and significantly impacted the course of Western civilization by preventing further Arab expansion into Europe.
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Siege of Constantinople (717-718)
Type of action: Arab expansion into Europe
Date: August 15, 717-August 15, 718
Location: Constantinople, Byzantium (later Istanbul)
Combatants: Byzantines vs. Arab Muslim forces
Principal commanders:Byzantine, Leo III (c. 680-741); Muslim, Maslamah ibn ʿAbd al-Malik (d. 738)
Result: Byzantine victory
Water on one side and high walls on the other protected Constantinople, capital of the Byzantine Empire. It could be taken only by blockade. Arab general Maslamah ibn ʿAbd al-Malik led an invasion of 80,000 men and 1,800 ships carrying another 80,000 infantry.
Maslamah entrenched outside Constantinople on August 15, 717, and began an attack. The outnumbered Christians, believing they were protected by Mary, mother of God, beat back the Muslims. Maslamah then sent his fleet to cut off access to the Aegean and Black Seas.
Leo III was lying in wait when the first squadron of ships traveling north was caught up in a current as they approached Seraglio Point. He attacked with a petroleum mixture called Greek fire before the blockade ships could form a battle line. He destroyed twenty ships and captured the others. No other ships approached. The stalemate allowed Leo III to supply the city.
Snow stayed on the ground for one hundred days that winter, killing thousands of Arabs. In the spring, a squadron of ships closed passage to the Bosporus, and a reserve army reinforced Maslamah’s trenches. Finally in place, the blockade might have worked, but Christians deserting from Arab ships gave Leo III information that allowed him to catch the blockade ships unprepared. As Leo III routed the Arab fleet, more Christians deserted by the thousands. Leo III followed the naval victory with a land pursuit aided by Bulgar allies.
Maslamah was recalled August 15, 718. During the retreat, his fleet was lost in a storm. It is believed that only five galleys and only 30,000 land forces returned.
Significance
One of the greatest successes in Roman history, these battles repelled an Arab invasion of the Eastern capital and saved Western civilization from being overrun by the forces of Islam.
Bibliography
Nicol, Donald MacGillivray. A Biographical Dictionary of the Byzantine Empire. London: Seaby, 1991.
Runciman, Steven. Byzantine Civilization. New York: Barnes & Noble, 1994.
Vasiliev, Alexander Alexandrovich. History of the Byzantine Empire, 324-1453. Madison: University of Wisconsin Press, 1990.