The Soviets were the first to find and liberate the camps on the Eastern Front and the rest of the Allies didn't believe them until they started to find them on the Western Front, so all of the Allied countries liberated them.
All Allies.
If you ever see Schindler's List its Soviets
who say "You are liberated!"
Jews: "where do we go now?"
Soviet: "Not here, they dont like you, not to poland, they dont like you there either, and not that way, because they do not like you"