The year is 1964, and World War I still continues. The Russian Baron von Ugenberg (based on the real-world Baron von Ungern-Sternberg, with a similar biography) conquered Mongolia in an uprising following the Russian Revolution. The alternate timeline began when he invaded Soviet Union, defeated the Bolsheviks, and founded a Russo-Mongolian state, with the eventual goal of capturing the whole of Europe. United States of Western Europe (the Alliance) were established to counter that plan. Lieutenant James Anderson, a veteran soldier who has been with the Alliance since the age of nineteen, is sent on a highly dangerous mission: breach the enemy's defense line, and prevent the Russo-Mongolians from developing a new nuclear weapon.
Iron Storm is an alternate reality-themed first-person shooter (with optional third-person controls). The gameplay strives to reflect realistic warfare, a mixture of World War I and World War II styles. Siege tactics, trenches, and mustard gas co-exist with machine guns, mortars, and other weaponry characteristic of World War II; more advanced technology such as wireless communications, automated turrets, and spy satellites, is also common. The hero has to rely on careful advancement, taking cover and trying to avoid or outsmart the more powerful enemies.