You can read about how Soviet dictator Joseph Stalin saved Polish Jews from the Nazi gas chambers in this recent news article: http://www.ibtimes.com/how-joseph-stalin-inadvertently-saved-some-polands-jews-1099571
The following quote is from the news article:
Soviet dictator Joseph Stalin, perhaps the worst mass killer in human history with the blood of tens of millions of people on his hands, once inadvertently saved Polish Jews from the Nazi death camps and gas chambers by deporting them to Siberia and other parts of the USSR.
In 1940, one year before the Nazis commenced their program of extermination, Stalin ordered the deportation of some 200,000 – perhaps as many as 300,000 — Polish Jews from Russian-occupied Eastern Poland to Gulag labor camps deep in the Soviet Union.
Notwithstanding his virulent anti-Semitism (and his own sanctioning of the killing of Jews within Russia itself), Stalin’s order ironically saved these Jewish lives – indeed, these deportees represented the bulk of Polish Jewry who survived the Nazi Holocaust.
In 1939, just before the outbreak of World War II, Poland boasted a Jewish population of some 3.3-million, or about 8.5 percent of the total (and almost one-third of Warsaw’s population).
How many of those Jews, who had been deported to Siberia, came back and settled in Poland where they told their stories of how they had been saved from the Nazi gas chambers?
You can see photos of all the Nazi gas chambers on this previous blog post: https://furtherglory.wordpress.com/2010/08/30/how-many-of-the-nazi-gas-chambers-are-still-in-existence/