1. King Leopold II of Belgium (1835–1909)
Leopold II is remembered for one of the darkest periods in colonial history. His personal rule over the Congo Free State led to the exploitation of millions of Africans in pursuit of rubber and ivory. The brutal regime he established caused millions of deaths due to forced labour, starvation, disease, and violent punishment. Under Leopold’s rule, entire villages were destroyed, and the use of mutilation as a punishment became infamous, with the cutting off of hands symbolising the horrors endured.
2. Genghis Khan (1162–1227)
Known as one of history’s greatest conquerors, Genghis Khan was also one of its most fearsome. His campaigns stretched across Asia and into Europe, leaving a trail of destruction in their wake. Genghis Khan’s armies were notorious for wiping out entire cities, and he is believed to have caused the deaths of millions. His ruthless military strategies and mass slaughter, such as in Nishapur, where nearly the entire population was killed, cemented his legacy as a figure of terror.
3. Ivan the Terrible (1530–1584)
Ivan IV, the first Tsar of Russia, lived up to his moniker “The Terrible” through his violent and erratic rule. Known for his paranoia and cruelty, Ivan created a secret police force, the Oprichnina, which carried out mass executions and enforced his authoritarian rule. His most infamous act was the Massacre of Novgorod, where thousands of citizens were tortured and killed, accused of treason. Ivan’s unpredictable violence extended to his own family, as he killed his own son during a fit of rage.
4. Attila the Hun (406–453)
Attila, leader of the Huns, was one of the most feared figures of the ancient world. His reign of terror across Europe earned him the nickname “The Scourge of God.” His brutal invasions of the Roman Empire involved widespread slaughter, pillaging, and destruction. Attila’s campaigns were marked by the sacking of cities and leaving devastation in his wake, making him one of history’s most infamous conquerors.
5. Emperor Nero (37–68 AD)
Nero’s reign as Roman Emperor is synonymous with decadence and cruelty. His erratic behaviour and harsh policies towards Christians earned him a dark legacy. Among his many cruel acts, Nero is most infamously associated with the Great Fire of Rome. While historical accounts differ, many believe Nero either caused or did nothing to stop the fire, which destroyed much of the city, allegedly playing music as Rome burned. His persecution of Christians, whom he blamed for the fire, led to brutal executions.
6. Shaka Zulu (1787–1828)
A brilliant military strategist, Shaka Zulu turned the Zulu Kingdom into a dominant force in Southern Africa. However, his reign was marked by extreme brutality, particularly towards neighbouring tribes. Shaka’s military innovations were accompanied by the destruction of rival tribes and large-scale massacres, which expanded his empire. His reign of terror earned him a reputation for being as ruthless as he was tactically brilliant.
7. Tamerlane (1336–1405)
Tamerlane (Timur) is known for his brutal conquests across Asia and the Middle East. His military campaigns, which aimed to restore the Mongol Empire, were characterised by the mass execution of populations and the destruction of cities. He was known for constructing towers out of the skulls of his enemies, most notably after the sack of Delhi. Tamerlane’s legacy is one of a brilliant but merciless conqueror who left death and devastation wherever he went.
As the leader of the Khmer Rouge in Cambodia, Pol Pot presided over one of the most brutal genocides of the 20th century. His regime aimed to transform Cambodia into a classless, agrarian society, but this vision resulted in the deaths of approximately 1.7 to 2 million people due to starvation, forced labour, and execution. Pol Pot’s reign of terror, which sought to erase any intellectual or cultural history, destroyed an entire generation.
9. Queen Ranavalona I of Madagascar (1778–1861)
Ranavalona I, often called the “Mad Queen,” ruled Madagascar with an iron fist. Her isolationist policies and mistrust of foreigners led to the deaths of thousands through execution, forced labour, and widespread famine. During her reign, about half of Madagascar’s population perished, earning her a place among the most brutal leaders in African history.
10. Francisco Pizarro (1476–1541)
The Spanish conquistador Francisco Pizarro is infamous for his ruthless conquest of the Inca Empire in South America. Driven by a desire for wealth, Pizarro captured and executed the Incan emperor Atahualpa, despite receiving a ransom of gold and silver. His conquest led to the collapse of the Incan civilisation and the death of thousands of indigenous people.
These ten leaders are remembered not only for their ambition but for the extreme cruelty they exhibited during their reigns. Their acts of violence, whether through conquest, persecution, or exploitation, have left scars that continue to echo through history, reminding us of the potential for power to corrupt and devastate on a massive scale.
