After 14 months of siege ,
Alexandria
was conquered by Muslim troops at the end of 642 . When the Muslim commander , Amr Ibn El As entered the city , he made an inventory of what Muslims found in the city: "4000 palaces , 4 , 000 baths , 12 , 000 merchants of oil , 12 , 000 gardeners , 40 , 000 Jews as well as 400 theaters and places of entertainment" . Some historians say that the
Arabs
destroyed the library of Alexandria , but the truth is that the library did not exist at the time . Rather , it was a victim of civil wars and earthquakes .