The best factual story from Stalingrad was Pavlov’s House, where Russian soldiers under Pavlov held off the Germans for days, with fighting even going on inside the house.
Pavlov found a discarded New Testament in the house, and after the war — despite being a Soviet hero — became an orthodox monk. Stalin apparently allowed this.
I don’t think I know that story, but it does ring a bell.
Did Pavlov have a dog by any chance?