Stalin

General Secretary of the Soviet Communist Party who transformed the USSR through forced industrialization and collectivization, killed millions through the Gulag and purges, led the Soviet victory over Nazi Germany, and established the postwar Soviet empire.

Stalin as the 20th century's most consequential authoritarian: his industrial transformation of the USSR (at the cost of millions of deaths through forced collectivization/famine and Gulag) created the military-industrial capacity that defeated Nazi Germany — possibly the single most important military outcome of WWII. His postwar consolidation of Eastern Europe created the Cold War framework. The paradox: Stalin's crimes were among the worst in human history, yet he also led the state that bore the greatest burden in defeating Hitler (27 million Soviet dead). Understanding his decision-making requires engaging with both dimensions without reducing one to the other.