In real life, Dick Winters kept the pistol given to him by the surrendering German officer. He noticed that it had never been fired through six years of war. He still owns the pistol and it has still never been fired. He shows it to the camera in the HBO documentary We Stand Alone Together.
The execution of the alleged camp commandant was similar to what's portrayed in the series but not entirely. Captain Speirs was told by former prisoners the location of this commander. Convinced this was accurate, Speirs sent Lynch, Liebgott, Sisk and Moone to kill him. When they arrived, Liebgott interrogated the suspect for half-an-hour. Satisfied this was their man, they loaded the prisoner on board their vehicle and drove away. Alongside a ravine, the prisoner was ordered out and Liebgott shot him twice. Somehow still alive, the prisoner ran up a hill. Moon was ordered to, but refused, to fire. Sisk fired instead and killed the fleeing man. Webster wasn't present for this and the prisoner's identity and his guilt has never been confirmed.
Eagle's Nest, Hitler's retreat above Berchtesgaden, where Easy Company is assigned, was little used by the Fuhrer as he was terrified of heights and disliked the cold, thin mountain air. Today, it doubles as a seasonal restaurant. It is one of the few undamaged monuments from the Nazi period.
The "company of heroes" quote is sometimes wrongly attributed to Dick Winters. While he's the one who delivers it in the ending interviews, he's quoting his friend Mike Ranney. It's Ranney who had the conversation with his grandson, not Winters.
While in Austria, Talbert asks "Are we to run up them (the mountains) or ski down them?" After WWII, the United States ski industry grew from the experiences of the returning soldiers stationed throughout Europe. Winters actually sent the men up the mountain with instructors to learn how to ski, just to keep them out of harm's way. Although the ski lift was inoperable, the mountain was scalable by the men.