Ashkenazi Jews added to the history of German Jewry in modern times in the abstract of his seminal work, "History of the Jews", which he entitled "Volksthümliche Geschichte der Juden." In an essay on Sephardi Jewry, Daniel Elazar at the Jerusalem Center for Public Affairs summarized the demographic history of Ashkenazi Jews in the last thousand years, noting that at the end of the 11th century, 97% of world Jewry was Sephardic and 3% Ashkenazi; by the end of the 16th century, the: 'Treaty on the redemption of captives', by Gracian of the God's Mother, Mercy Priest, who was imprisoned by Turks,
Ashkenazi Hebrew from Spain in 1492 (or before) the Sephardic pronunciation of the vowels became standard in all these countries, ironing out any differences that previously existed. This makes it harder to adjudicate between the different theories on the relationship between today's pronunciation systems and those of ancient times. Leopold Zunz believed that the Ashkenazi pronunciation was derived from that of Palestine in Geonic times (7th–11th centuries CE), while the Sephardi pronunciation was derived from that of Babylonia. This theory was supported by the fact that, in some respects, Ashkenazi Hebrew resembles the western dialect of Syriac while Sephardi Hebrew resembles the