The destructive tsunami that hit Alexandria in 365 caused incalculable damage, but the city survived. Its position on the shores of the Mediterranean made it a valuable acquisition, and many empires fought hard to control it. In 619, it fell to the Sassanid Persians, only to be recaptured by the Byzantines (heirs to the Roman Empire) ten years later. Egypt was the granary of their empire, and Alexandria served as a major military and naval base. But their rule was not meant to last. In 641, the Muslim armies of the general 'Amr ibn al-'As (c. 573-664) captured the city after a six-month siege. By then, the majority of the population were Coptic Christians. The new Muslim rulers made an effort to respect their religious and cultural traditions, ushering into a long period of renewed prosperity. Greek, Coptic, and Arabic were freely spoken in the streets, while Christians of various sects and Muslims coexisted in relative harmony.