Rabbi Moshe Feinstein was one of the major leaders of American Jewry in the 20th century. Born in 1895, he came to New York in 1936 in order to escape the oppressive Soviet regime. In addition to the students in the yeshivah he headed, he guided rabbis and lay people with his insightful and definitive responsa on virtually every area of Jewish law. Many of them have been collected in the multi-volume Igrot Moshe. Chassidim, a collection of ethical and halachic teachings that is widely studied to this day.