The vast territories of 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 antisemitic discriminatory policies and persecutions. Russian Jewry consists predominantly of Ashkenazi Jews but also comprises a number of other Diasporan Jewish groups, such as Mountain Jews, Crimean Karaites, Krymchaks, Bukharan Jews, and Georgian Jews.