The medieval city corresponded to what is now known as the Old City (expanded in the 2nd century as Roman "Aelia Capitolina"). Population at the time of the Muslim conquest was about 200,000, but from about the 10th century it declined, to less than half that number by the time of the Christian conquest in the 11th century, and with the re-conquest by the Khwarezmi Turks was further decimated to about 2,000 people (moderately recovering to some 8,000 under Ottoman rule by the 19th century).