This camp was liberated by Patton's Third Army. This from Wiki:
Among the inmates liberated from the camp was Lieutenant Jack Taylor, an officer of the Office of Strategic Services. He had managed to survive with the help of several prisoners and was later a key witness at the Mauthausen-Gusen camp trials carried out by the Dachau International Military Tribunal. Another of the camp's survivors was Simon Wiesenthal, an engineer who spent the rest of his life hunting Nazi war criminals. Future Congressional Medal of Honor winner Tibor "Ted" Rubin was imprisoned there as a young teenager; a Hungarian Jew, he vowed to join the U.S. Army upon his liberation and later did just that, distinguishing himself in the Korean War as a corporal in the 8th Cavalry Regiment, 1st Cavalry Division.
A great man.