“How the Steel Was Tempered” is a  socialist realist novel written by Nikolai Ostrovsky (1904–1936). With 36.4 million copies sold, it is one of the best-selling books of all time and the best-selling book in the Russian language.

The story follows the life of Pavel Korchagin, including his fighting in and aftermath of the  Russian Civil War  when he fought for the Bolsheviks during the war and was injured. The novel examines whether or not Korchagin can heal from his wounds and thus become as strong as steel.