The history of the Jews in Russia and areas historically connected with it goes back at least 1,500 years. Jews in Russia have historically constituted a large religious and ethnic diaspora; the Russian Empire at one time hosted the largest population of Jews in the world. Within these territories the primarily Ashkenazi Jewish communities of many different areas flourished and developed many of modern Judaism's most distinctive theological and cultural traditions, while also facing periods of anti-Semitic discriminatory policies and persecutions. Some have described a 'renaissance' in the Jewish community inside Russia since the beginning of the 21st century. And today, Russia's Jewish population is still among the largest in Europe.