How come, during World War 2, that the Germans were able to keep concentration camps, and the holocaust, a secret?

by grotefluit

You would imagine that some facts would leak out. As far as I know, the Russians were the first to find out about the mass destruction camps when they were reconquering Eastern Europe.

estherke

Some facts did leak out. Here are some answers I wrote a while back about who knew what and how and when: one, two, three.