Prior to World War II, Opatów had a substantial Jewish population. Known as 'Apt' in Yiddish, Opatów became home to 6,000 Jews with a history of rich cultural and religious life. Best known from among the locals was the 18th century Rabbi Avraham Yehoshua Heshel ("Apter Rebbe"), who was instrumental in the development of the Chasidic movement, and the famous Noda Be'Yehuda of Prague, one of the leading halakhic authorities of 18th Century Europe. Jewish life in Apt has been chronicled by Professor Gershon Hundert in his 1992 book "The Jews in a Private Polish Town", drawing upon a variety of sources from the history of Jews in Poland. The work describes the demographic and historical background as well as the structure of the Jewish community of Apt (Opatów) with a population numbering about 2,000 in 1765, exceptionally large for any Jewish shtetl in the 18th century Europe. The town's Jewish inhabitants enjoyed considerable prominence also in the following centuries. Hundert uses the Jewish Opatów as a case study for Polish Jewry. More than three-quarters of them lived on private lands of powerful magnate aristocrats known as the Szlachta. Hundert's work also describes the vibrant interaction of the Jews of Apt with their Polish Christian neighbours. It is a challenge to previous historiography which describes Jewish life in Poland in alleged isolation.