For nearly a thousand years, the Byzantine Empire protected Europe from Islamic powers, allowing it to pursue its own destiny, and Byzantium was a polyglot society in which a multitude of ethnic groups lived under the emperor prizing peace above war. Of course, it wasn't an accident that Constantinople survived for so long. Since ancient times, settlements have been protected by walls, ranging from simple earth fortifications, mounds, and ditches to sophisticated structures incorporating gates and watchtowers.
Amid the upheaval in the Islamic world following Muhammad's death, the Umayyad Caliphate lasted for less than a century, but it spent that time becoming one of the most influential of the major caliphates. The Umayyads also constantly fought the Byzantines, and on August 15, 717, their formidable army, under the command of General Maslama ibn 'Abd al-Malik, arrived in Thrace and laid siege to the imposing walls of Constantinople. This event, which lasted a full year until August 15, 718, represented the apex of the Islamic expansionist project aimed at definitively eradicating the Byzantine Empire and subjugating its seemingly impregnable capital. The siege of 717–718 was of great significance, marking a crucial and irreversible turning point in the history of Europe and the Middle East.
The remarkable resistance of Constantinople was not just a stroke of good fortune, but a decisive turning point that permanently halted the Islamic expansion into Eastern Europe. The Byzantine victory was the result of a potent blend of military architecture, technological superiority, environmental conditions that were disastrous for the invaders, and astute strategic diplomacy. The definitive failure of the invasion project ultimately forced the caliphate to abandon the idea of conquering the Byzantine Empire.
