Evidence suggests that while Jews have lived in southern and western regions of the Russian Empire since the 4th century, a significant population didn’t arrive in Muscovy until the 15th century. The largest influx of Jews came with annexation of Polish territories in 1793 and 1795. In an effort isolate these populations, the Catherine the Great instituted the Pale of Settlement, which prohibited Jewish residence outside of these areas. In the late 19th and early 20th century persecution and poor economic conditions encouraged millions of Jews to emigrate. Nevertheless, by 1897, about one-half of the world’s Jewish population, or 5,189,400 Jews, lived in the Russian Empire. Today, that number has fallen to between 400,000 and 700,000.