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Asiatic Vespers, 88 BCE -

In what is considered one of the deadliest recorded genocides in Classical antiquity, forces loyal to Mithridates VI (132–63 BCE), ruler of the Kingdom of Pontus, massacred an estimated 80,000 Roman and other Latin-speaking peoples living in parts of western Anatolia in 88 BCE. The prolonged slaughter became known as the Asiatic Vespers and provoked the First Mithridatic War (89–85 BCE) between the Roman Republic and the Kingdom of Pontus.

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Massacre of the Rhineland Jews, 1096 -

The Rhineland massacres were a series of mass murders perpetrated by mobs of German Christians during the People's Crusade, the early phase of the First Crusade, from April to October 1096. Around 12,000 perished in what if often regarded as the first in a sequence of anti-Semitic events in Europe that culminated in the Holocaust.

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Massacre of the Latins, 1182 -

A brutal killing spree known as the Massacre of the Latins took place in 1182 when the Eastern Orthodox population of Constantinople turned on their Roman Catholic neighbors. Around 60,000 were slain, and the massacre further worsened relations and increased enmity between the Western and Eastern Christian churches.

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Lisbon massacre, 1506 -

On April 19, 1506, the carnage that became known as the Lisbon massacre began when roving mobs of Catholics persecuted, tortured, killed, and burnt at the stake hundreds of people who were accused of being Jews. Nearly 2,000 died. The lives lost are commemorated with this monument located in Lisbon's Largo São Domingos.

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Cholula massacre, 1519 -

In one of the most ruthless actions of Hernán Cortés (1485–1547) in his campaign to conquer Mexico, hundreds of unarmed Aztec noblemen were slaughtered by Spanish conquistadors, assisted by Cortes' Tlaxcalan allies as the Cholulans were their traditional enemies. Within hours, thousands of inhabitants of Cholula were dead.

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St. Bartholomew's Day massacre, 1572 -

Plotted by Catherine de' Medici (1519–1589) and carried out by Roman Catholic nobles and other citizens, the St. Bartholomew's Day massacre resulted in the deaths of thousands of Huguenots (French Calvinist Protestants). In fact, modern estimates for the number of killed across France during the summer of 1572 vary widely, from 5,000 to 30,000.

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Yangzhou massacre, 1645 -

The events that took place at Yangzhou are regarded by most scholars as the greatest single incident massacre in history. On May 10, 1645, Qing dynasty forces under the command of Dodo, Prince Yu attacked the city of Yangzhou and killed 800,000 innocent civilians over the next 10 days. Pictured is a late-Qing woodblock print representing the massacre.

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Praga massacre, 1794 -

Known also as the Second Battle of Warsaw, the Praga massacre was an assault by Russian forces on Praga, a suburb of Warsaw, during the Kościuszko Uprising in 1794. Anywhere between 7,000 and 20,000 civilians were murdered.

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Boston massacre, 1770 -

The Boston massacre was a deadly riot that occurred on March 5, 1770 when a large gathering of unarmed colonists were fired upon by British soldiers. While only five demonstrators lost their lives, the shooting was used by propagandists to lobby for independence from England.

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Peterloo massacre, 1819 -

The Peterloo massacre took place at St Peter's Field in Manchester, England, on August 16, 1819. Around 60,000 peaceful pro-democracy and anti-poverty protesters were charged at by cavalry ordered to disperse the crowds. Eighteen people died in the attack.

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Chios massacre, 1822 -

One of history's most tragic and comprehensive acts of genocide took place on the Greek island of Chios in 1822 when tens of thousands of Greeks were massacred by Ottoman troops during the Greek War of Independence (1821–1829).

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Wounded Knee massacre, 1890 -

The Wounded Knee massacre is named for the slaughter of approximately 150–300 Lakota Indians by United States Army troops in the area of Wounded Knee in South Dakota on December 29, 1890. Pictured in 1940 is a crude sign commemorating the event. The Wounded Knee battlefield was eventually declared a US National Historic Landmark in 1965.

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Hamidian massacres, 1894–97 -

The Hamidian massacres relate to the genocide inflicted upon the Armenians between 1894 and 1897 by Ottoman forces that resulted in the deaths of up to 300,000 people. The massacres are named after Sultan Abdul Hamid II (1842–1918), who signed off on the carnage.

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Wilmington massacre, 1898 -

On November 10, 1898 an armed mob of white supremacists burned down the offices of the Daily Record, a black-owned newspaper operating out of Wilmington in North Carolina. The insurgents then moved into the streets and opened fire as African-American citizens fled for their lives. Finally, the rabble seized control of the racially-mixed city government in what historians have described as a coup d'état. As many as 300 residents of color lost their lives.

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Ludlow massacre, 1914 -

The Ludlow massacre was an attack on striking coal miners and their families by the Colorado National Guard and private Colorado Fuel and Iron Company guards at Ludlow, Colorado, on April 20, 1914. Twenty-one people died in the violence, including women and children, which was orchestrated by billionaire industrialist John D. Rockefeller Jr., a part owner of the company operating the coalfields.

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Jallianwala Bagh massacre, 1919 -

The killing of hundreds of unarmed Indians shot by British troops while attending a public meeting at the Jallianwala Bagh in Amritsar, Punjab, to protest against the arrest of pro-Indian independence leaders stunned the entire nation.

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Tulsa race massacre, 1921 -

The Greenwood district of Tulsa, Oklahoma, was the scene of what was later described as one of the single worst incidents of racial violence in US history after mobs of white residents attacked their black neighbors and destroyed homes and businesses on May 31, 1921. An estimated 200 people of color lost their lives, as did around 50 white residents. A further 10,000 African Americans were left homeless.

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"Saint Valentine's Day Massacre," 1929 -

Surely one of the most over-reported and glamorized killings of the 20th century, the "Saint Valentine's Day Massacre," as it was labeled, was a hit ordered by Chicago mobster Al Capone on seven members of a rival gang during the Prohibition era. Pictured is the store-garage where the shootings took place. It was demolished in 1967.

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Nanjing massacre, 1937–1938 -

The atrocities committed by Imperial Japanese troops against the residents of the Chinese city of Nanjing in December-January of 1937–38 constitute one of the greatest crimes against humanity in world history. Estimates of Chinese dead number up to 300,000. The attack was allegedly ordered by Prince Yasuhiko Asaka (1887–1981), seen here in 1935, but he was never charged.

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Katyn massacre, 1940 -

Numerous atrocities took place during the Second World War, but one singe incident massacre stands out: Katyn. In April and May of 1940, members of the NKVD, the Soviet secret police, murdered 22,000 Polish military officers and intelligentsia in the Katyn Forest near the city of Smolensk. Their mass graves were uncovered by German forces in 1943, and the Nazis were blamed for the massacre until 1990, when Russian authorities finally acknowledged the crime and the subsequent near 50-year cover-up by the Soviet government. 

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Oradour-sur-Glane massacre, 1944 -

As retaliatory action goes, few deeds come close to that visited upon the residents of the French village of Oradour-sur-Glane by the Nazis on June 10, 1944. After learning that one their colleagues had been captured by the French Resistance in another village, members of a Waffen-SS unit murdered over 600 residents before razing Oradour-sur-Glane to the ground. After the war, President Charles de Gaulle ordered that the ruins of the village be maintained as a permanent memorial and museum.

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Malmedy massacre, 1944 -

Another atrocity carried out by the Waffen-SS was the summary execution of 84 US Army prisoners of war on December 17, 1944 near the Belgian city of Malmedy. Pictured on trial at Dachau after the war are some of SS combatants involved in the massacre.

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Hill 303 massacre, 1950 -

The Hill 303 massacre was a war crime perpetrated by North Korean soldiers during the opening salvos of the conflict when 40 American prisoners of war were shot and killed on a hill above Waegwan in South Korea.

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Sharpeville massacre, 1960 -

The Sharpeville massacre occurred on March 21, 1960 at the police station in the South African township of Sharpeville in Transvaal (today part of Gauteng). After a day of demonstrations against the Pass Laws, a crowd of about 5,000 to 7,000 black protesters gathered outside the building. The South African police subsequently opened fire on the crowd, killing 69 people.

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University of Texas tower massacre, 1966 -

On the morning of August 1, 1966, Charles Whitman climbed to the top of the University of Texas Tower in Austin and began shooting indiscriminately at pedestrians below. In all, 15 people died that day, including Whitman's mother and wife, whom he had murdered earlier. Whitman was eventually shot and killed by Austin police officers. The incident was one of the worst mass murders in a public area in the history of the United States and the first to unfold "live" in the era of mass media.

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My Lai massacre, 1968 -

One of the most shameful episodes in the history of the US military took place on March 16, 1968 when a company of American soldiers entered the village of My Lai in South Vietnam and massacred around 500 men, women, and children. The incident prompted global outrage when it became public knowledge in November 1969. 

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Bogside massacre, 1972 -

Better known as Bloody Sunday, the Bogside massacre of January 30, 1972 saw 13 unarmed civilians shot dead by members of the British Army in Derry, Northern Ireland. Pictured are the coffins of some of victims laid out in a church.

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Munich massacre, 1972 -

This is one of the defining images of the Munich Olympics in 1972, snapped after members of the Palestinian terrorist group Black September took 11 members of the Israeli Olympic team hostage. The athletes were later killed by their captors at Fürstenfeldbruck Air Base.

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Sabra and Shatila massacre, 1982 -

The killing of between 460 and 3,500 civilians, mostly Palestinians and Lebanese Shiites, by the militia of Lebanese Forces in the Sabra and Shatila refugee camp in Beirut was met with widespread condemnation. The massacre took place on September 18, 1982 in plain sight of the Israeli Defense Forces, the militia's ally.

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Srebrenica massacre, 1995 -

Thousands of shovels are seen stacked symbolically in the Srebrenica–Potočari Memorial and Cemetery for the Victims of the 1995 Genocide. The cemetery near Srebrenica is the final resting place of around 6,000 of the more than 8,000 Muslim men and boys who were killed in the July 1995 Srebrenica massacre.

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Port Arthur massacre, 1996 -

Australia was rocked to its core in April 1996 after a lone gunman, Martin Bryant, went on a killing spree and murdered 35 people in Port Arthur, Tasmania. He was eventually apprehended at the Seascape Guesthouse (pictured), which is now a memorial site. The episode remains the worst massacre in modern Australia committed by a single person.

Sources: (Haaretz) (History and Headlines) (Peterloo Massacre) (Zinn Education Project) (Britannica) (BBC) (Tulsa History) (Holocaust Encyclopedia) (History)

See also: The most mysterious murders of all time

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