In real life, Iosif Stalin was born as Iosif Vissarionovich Dzhugashvili. He adopted the name Stalin, which means Man of Steel. He is considered to be the second-biggest mass murderer in history, behind only Mao Zedong, as he is responsible for the deaths of around 20-60 million Russian/Soviet citizens and even military officers, including high-ranking ones like Mikhail Tuckachevsky and Nicolai Yezhov in The Great Purge.
During World War II, Stalin was nearly defeated by Hitler, the latter's Wehrmacht nearly capturing Moscow and inflicting massive casualties on the Red Army. However, after the German advance was finally repelled in the battles of Kursk and Stalingrad, the Red Army then broke the Siege of Leningrad and fought back the Germans, with the Soviets reaching Berlin during the middle of April 1945.
Before becoming a dictator, he organized several bank robberies in his native home country of Georgia.
From 1926 to his death in 1953, Stalin ruled the Soviet Union with an iron fist, creating a cult of personality and executing millions upon millions of Russians. When he died in 1953, his successor Nikita Khrushchev then started the de-Stalinization process, eliminating the cult of personality and balanced the Soviet economy, as Stalin largely focused on his army.
Stalin lived from December 18 1878 to March 5 1953. He died of cerebral hemmoraging, though there are also claims that he died of a heart attack, stroke, lung cancer and even poisoned or assassination by a firearm.