Constantinople (Moslem Invasion of Europe).
This city was besieged in 668, by the Saracens under Sophian, the lieutenant of the Caliph Moawiyeh. The Moslem fleet passed the Hellespont unopposed, but their attack upon the city was met with a most determined resistance. After keeping the field from April to September, Sophian retired into winter quarters, but renewed active operations during the following and five succeeding summers, without success, until, in 675, he finally abandoned the siege, having lost in its progress over 30,000 men.
In 716, the Saracens again laid siege to the city, with 120,000 men under Moslemeh, brother of the Caliph Solyman. A fleet of 1,800 sail co-operated with the land forces, but was destroyed by the Greek fire ships, and thus obtaining the command of the sea, the citizens were relieved from all fear of famine, and repulsed all Moslemeh's assaults. After a siege of 13 months, the Saracens withdrew, after a defeat at the hands of a Bulgarian relieving army, in which they lost 22,000 men.