The film depicts Zaitsev as a bit of an unschooled simpleton, from some backwater part of the country, but who knew how to shoot a rifle. In reality, Vasily Zaitsev was an educated man, and had worked for five years as an accountant in the Russian navy stationed in the Pacific before joining the army.
In the large battle scenes it was deemed too dangerous with so many extras in a confined space to set off explosions by remote. Stuntmen were mixed in with the extras to set off the explosions by stepping on pressure plates.
It is estimated that the Axis suffered 260,000 soldiers killed in action with 90,000 captured during the Battle of Stalingrad. The Soviet casualties were much more severe with an estimated 500,000 soldiers killed and probably at least as many civilians.
Major König, played by Ed Harris, can be seen wearing gloves with the index finger and thumb on its right hand removed. This was quite common for snipers in cold conditions as it helped prevent frostbite in the hand, while allowing them to make delicate changes to their weapon and ensuring a smooth trigger squeeze.