Bila Tserkva is the largest town in Kiev Oblast. The Bila Tserkva massacre was the World War II mass murder of Jews, committed by the Nazi German Einsatzgruppe with the aid of Ukrainian auxiliaries, in Bila Tserkva, Soviet Ukraine, on August 21–22, 1941. This was not the only incident of anti-Jewish hate in this region. Many Jewish people had moved to the region from Poland and Germany and other places further west to help manage land owned by absentee landlords from Poland and Lithuania during the 16th Century. Between 1569 and 1648 the number of Jews in Ukraine increased from about 4,000 to nearly 51,325, dispersed among 115 towns and settlements. In 1648 the Cossacks led by Bohdan Khmelnytsky which led to pograms that lasted until the early 20th century and the masacres of perhaps 30 to 50 thousand Jewish souls. Chassidism was started in the Ukraine by the Baal Shem Tov (Israel ben Eliezer) in the 1770s and the movement spread quickly. Chassidism with its roots in kabbalah, miracles and spiritual Judaism, was a popular alternative to traditional Rabbinic Judaism with its basis in deep learning. Rabbi Nachman is buried in Uman although he only lived a few months here.