The collection includes materials from a scientific conference organized by the International Research Center for Russian and East European Jewry, held in December 2006 in Moscow. The book presents articles by researchers from Russia, Belarus, Great Britain, Germany, Israel, the United States. At the end of the XIX century. more than half of all Jews in the world lived in the Russian Empire. 1881 was the starting point for the mass emigration movement from tsarist Russia. Emigration continued in Soviet and post-Soviet times, again becoming massive in the last third of the XX century.