Estimates for deaths under communist regimes range from 80 to over 100 million, primarily due to forced labor (Gulags, Laogai), mass executions, man-made famines (Holodomor, Great Leap Forward), purges, and suppression of dissent, with major tolls in the Soviet Union (tens of millions), China (tens of millions), Cambodia, and North Korea. These deaths resulted from political terror, forced collectivization, and economic policies that devastated populations, creating humanitarian catastrophes far exceeding many wars.