In September 1939 he was one of the seven rabbi chaplains in the Polish Army . During the Polish September Campaign he was the Chief Chaplain for Noncatholics in the Army Kraków and chief rabbi of the Polish army . He was taken prisoner by the Soviets after the Soviet invasion of Poland in late September , becoming a prisoner of war . He was imprisoned in the camp in Starobilsk . In Starobilsk he organized services for his fellow inmates , which were also attended by non-Jewish Poles ; survivors noted his emphasis on unity of all Poles , regardless of religion . In Starobilsk , Steinberg was arrested by NKVD together with Polish priests and chaplains during Christmas of 1939 and transported to a prison in Moscow . He briefly returned to Starobilsk in March 1940 , and then was moved to Yukhnov and later to Kozelsk camps . Steinberg was eventually murdered in the Katyn massacre , probably on 12 April 1940 , aged 42
Katyn massacre
Katyn massacre
Baruch Steinberg