Wendy Lower, historian and author of several books on the second world war and the Holocaust, calls them “the missing missing” – the Jewish men, women and children murdered in mass open-air shootings by Nazi death squads in such large, unrecorded numbers in so many places that even finding out quite how many were killed and where – let alone such identifying details as their names – is an almost impossible task. Ukraine: Holocaust Ground Zero lays out what is considered to be the beginning of the mass execution of Jews under Hitler’s regime, which would lead eventually to the...