The Allies betrayed General Patton, too, and may have had him killed (or Stalin did) because he hated the Russians and thought they were more evil bastards than the Nazis (and that is saying something!). (Target Patton).
Eisenhower and Montgomery were in bed with the Communists utterly ignoring their atrocities and trying to foil Patton’s every move all during the war. Made Patton puke and he was going to Congress to bring all their traitorous actions to light. Eisenhower, who had Presidential ambitions, wanted him to shut up. If Patton would have been listened to...WWII (by many top historian’s estimates) would have ended at least a year earlier and saved hundreds of thousands of Allied lives. Patton was a genius and the most common question of the Axis Powers was, “Where is Patton?”
I am ashamed to say it, but the Allies knew about the holocaust and did nothing to stop it because of the resource drain it was on the Axis. The victims represented another potential 3 million Axis troops and tens of thousands of educated professionals. in the big picture they were expendable and the Popes efforts to save them ran counter to Allied interests.