 Even so, the city was not to be entirely Muslim, at least not until the late 20th century.Slavs, Greeks, Jews and Armenians, all of whose diverse skills were needed, were allowed to settle in a city which was to become known as "alem penah"-refuge of the universe.According to the census of 1477, there were 9,486 houses occupied by Muslims; 3,743 by Greeks; 1,647 by Jews; 267 by Christians from the Crimea, and 31 Gypsies.