In 1945, Army medic LeRoy "Pete" Petersohn, just 22 years old, played a pivotal role in liberating the Nazi concentration camp Mauthausen. His firsthand account, captured in a letter to his family, vividly documented the atrocities he witnessed, including mass graves and the skeletal remains of prisoners. Petersohn's son believes his father felt an obligation to record these horrors for future generations, underscoring the importance of remembering such dark chapters in history to prevent future atrocities. This story highlights the enduring impact of individual testimonies in preserving the truth of history's most harrowing events.