Throughout history, humanity has witnessed its fair share of ruthless killers. Some of them ruled entire nations and were responsible for the deaths of millions. Others operated alone, taking lives as soldiers or as serial killers. But among these deadly figures, who is responsible for the highest number of deaths in human history?
Contenders for this grim title include notorious figures like Genghis Khan, Adolf Hitler, and King Leopold II. Also in consideration are individuals like Simo Häyhä — widely known as the most lethal sniper in history — and Colombia’s Luis Garavito, a serial killer whose crimes shocked the world.
In the sections below, you’ll find out who killed the most people in history — whether through political control or personal violence — and the methods they used.
Who Killed The Most People In History?
Who killed the most people in history? People often suggest Nazi leader Adolf Hitler or Soviet dictator Joseph Stalin, both of whom saw millions die as a direct result of their policies. But recent scholarship suggests that the world’s most murderous leader is China’s Mao Zedong.
Mao Zedong, the founding father of the People’s Republic of China, ruled the nation from 1949 until his death in 1976. In his quest to transform China into a leading Communist state, Mao enforced a series of draconian reforms. The BBC notes that he nationalised industries, turned private farms into collective ones, and harshly punished dissenters.
In 1958, Mao launched the “Great Leap Forward”, a campaign designed to accelerate industrial and agricultural productivity. However, the policy backfired catastrophically. Millions of citizens were displaced, many suffered harsh punishments, and widespread famine ensued. Even minor offences were met with brutal consequences, including torture and execution. Historian Frank Dikötter, in his book Mao’s Great Famine, estimated that between two to three million people were tortured or murdered during this period for minor infractions.
Dikötter cited one such chilling case: in a village in Hunan, when a young boy stole a bit of grain, the local official ordered his father to bury him alive. The man passed away from grief a few days later.
As for the total number of deaths, Dikötter believes that Mao’s policies led to the demise of “at least 45 million people between 1958 and 1962.” Some estimates suggest the figure could be as high as 78–80 million. Whichever number is accepted, it places Mao at the top of history’s list of deadliest individuals.
Other Leaders Who Killed People En Masse
Mao Zedong may have killed the most people in history, but other leaders have similar body counts. One such leader is Genghis Khan.
A depiction of Genghis Khan during combat.
During his rule between 1206 and 1227, the Mongol Emperor and his sons succeeded in creating the largest contiguous land empire in human history. And they relied more on violence than diplomacy to conquer territory.
According to History, censuses from the Middle Ages suggest that China lost tens of millions of people during Khan’s reign, and Genghis Khan’s Mongol forces may have wiped out a jaw-dropping 11 percent of the world’s population. Though the total death toll under his rule is difficult to determine, historians estimate that some 40 million people died as he expanded his empire.
That makes Genghis Khan one of the deadliest killers in world history. Other infamous leaders have much lower — but still horrific — death counts.
Joseph Stalin, the Soviet leader from the 1920s to 1953, is believed to be responsible for the deaths of between six and 20 million people. His regime was marked by brutal purges, engineered famines, forced labour camps, and mass executions.
Adolf Hitler, the dictator of Nazi Germany, orchestrated the genocide of approximately 11 million people during the Holocaust, targeting Jews, Roma, disabled individuals, and other marginalised groups. The broader Second World War caused an even greater number of casualties.
King Leopold II of Belgium oversaw atrocities in the Congo Free State that resulted in the deaths of eight to 11 million Congolese people. Meanwhile, Cambodia’s Pol Pot directed a genocide from 1975 to 1979, which led to the deaths of around 1.5 to 2 million people.
Soldiers And Serial Killers With High Kill Counts
While tyrannical rulers like Mao or Stalin had the power to enact deadly policies, some individuals killed staggering numbers with their own hands.
One such person is Simo Häyhä, a Finnish sniper known for his deadly precision during the Winter War against the Soviet Union between November 1939 and March 1940. Using only an iron sight and blending into the snow-covered terrain, Häyhä reportedly killed between 500 and 542 enemy soldiers over the course of about 100 days, making him the most successful sniper in history.
In contrast, some killers acted out of personal compulsion rather than wartime duty. Luis Garavito, for instance, is regarded as the most prolific serial killer ever recorded. Operating in Colombia between 1992 and 1999, he raped, tortured, and murdered an estimated 100 to 400 young boys. He officially confessed to 140 killings.
Similarly, Pedro Lopez — another Colombian serial killer — claimed to have murdered over 300 girls. Convicted of killing 110, Lopez later admitted to many more crimes, earning him the nickname “Monster of the Andes”.
In comparison, infamous American serial killers such as Ted Bundy and Jeffrey Dahmer are responsible for far fewer deaths, though their crimes were equally horrifying in nature.
So, who killed the most people in history? In terms of political leaders, Mao Zedong holds the grisly record, having caused the deaths of at least 45 million through catastrophic reforms. Among individual killers, names like Simo Häyhä and Luis Garavito stand out due to the sheer number of lives they ended.
Still, behind these statistics are human beings — people with families, dreams, and futures that were cruelly cut short. Understanding the scale of such atrocities means not just counting victims, but also remembering their humanity.
