The Deadliest Catastrophes In Modern History: 34 Heartbreaking Photos

Instead he looted the area for rubber and ivory, extracted with native labor under threat of death or dismemberment: Anyone who failed to deliver their quota was liable to have a hand chopped off, or worse.

British missionaries and activists eventually spread the word about the horror, leading the great powers to force Leopold to give up the colony – until then, his personal property – to the Belgian government.

This photo of a mutilated laborer was taken by missionaries in order to document the brutality.

The United States became involved in 1916 after Pancho Villa (pictured, at an insurgent camp in 1915), a rebel general, conducted cross-border raids killing scores of Americans.

Ultimately, the conflict resulted in The Mexican Constitution of 1917, which remains in place to this day.

Later Italy and the Ottoman Empire joined in, but nobody was able to break through the bloody stalemate of trench warfare.

German submarine attacks provoked the United States to declare war in April 1917, and American manpower finally helped turn the tide on the Western Front in 1918.

However, the unfair Versailles Treaty that ended the war left the losing side, Germany, nursing a grudge, ultimately leading to World War II.

World War I also saw the first major genocide of the 20th century, when the Ottoman government murdered approximately 1.5 million Armenians.

Pictured: Australian soldiers walk through the Chateau Wood near Ypres, Belgium in 1917.

Much of the fighting took place along railroad lines with armored trains, and disruption to transportation networks caused mass starvation (pictured: hungry orphans living on the street).

Eventually, the fighting ended with the triumph of the Reds and the formation of the Soviet Union.

The global influenza pandemic of 1918-1920 was probably caused or intensified by World War I, which brought both unprecedented global movements of people and health crises due to food shortages and other diseases.

The flu pandemic came in three distinct waves, peaking in late 1918, when it killed around 25 out of every 1,000 people infected.

Pictured: starving mother and child refugees from Shandong. 1930.

Pictured: Boats navigating flood waters in Hankou (now part of Wuhan) in central China. September 1931.

Meanwhile, endless political purges prevented anyone from growing powerful enough to challenge Stalin’s hold on power. His henchmen also murdered around 20,000 Polish military officers and intellectuals after dividing Poland with Hitler in 1939 (pictured: the Katyn massacre of Polish nationals, 1940).

At the same time that unprecedented numbers of troops took the battlefield, Axis powers carried out programs of genocide against civilian populations. The extreme racism of the Nazi ideology resulted in the deaths of some 6 million Jews along with five million other “undesirables” during the Holocaust. In Asia, the Japanese killed between 15 and 20 million Chinese citizens starting in 1931 with the Japanese invasion of Manchuria, along with millions more in other occupied countries.

Pictured: Dresden, Germany after the Allied firebombing on February 13-15, 1945.

Pictured: A child lies down on the sidewalk, too exhausted and sick to feed himself.

Pictured: Vultures feeding on corpses lying abandoned in an alleyway after bloody rioting between Hindus and Muslims. Circa 1946.

Pictured: A Swedish classroom with most of the class out sick due to the flu.

So, across China, rural communes gave up producing food to forge steel in jerry-rigged furnaces, while other communes worked “overtime” to produce more food to feed them. The result was mass starvation and a bunch of useless steel nuggets.

Pictured: Peasants in Xinyang show their zeal farming under floodlights. 1959.

Pictured: Thich Quang Duc, a Buddhist monk, burns himself to death on a Saigon street to protest alleged persecution of Buddhists by the South Vietnamese government. June 11, 1963.

Pictured: A sword-like knife used to kill communists, called a parang, being thrown by a young college student.

Pictured: Red Guards strike a dramatic pose.

It was an unusual Cold War conflict because the USSR and Britain both supported the Nigerian government, while France and other countries supported the Biafrans and other European mercenaries also played a prominent role as well.

Pictured: Two foreign hostages under guard by Nigerian federal troops in Port Harcourt in 1968.

Pictured: An American couple looks at a public health billboard in Des Moines, Iowa.

Pictured: An advertisement for a George Harrison record meant to raise funds and awareness in the name of the war.

Pictured: Defeated and injured Ethiopian soldiers after the 1991 overthrow.

The Khmer Rouge stayed in power after the genocide, and remained there into the 1990s.

Skulls lie in the killing fields of Choeung Ek. 1981.

Pictured: Angolan children in a military parade. 1976.

Following the Soviet withdrawal in 1989, civil war continued with the mujahideen eventually emerging victorious.

A wounded mujahideen fighter reaches out for help. 1989.

In the end, both countries were left with a military stalemate and no significant territory having changed hands.

Pictured: Basij (mobilized volunteer forces) women in black chador carry rocket launchers.

Then, it may have spread via global transportation networks: sailors may have brought the disease from Africa to Haiti in the 1950s or 1960s, and then the U.S. It was first identified in the U.S. among gay men in big cities in the early 1980s.

Anti-retroviral drugs debuted in the 1990s, radically changing the prognosis for patients and helping to bring the epidemic under control, despite the fact that it still claims disproportionate amounts of lives in the world's poorer, less-developed regions, namely in Africa.

Pictured: The AIDS Memorial Quilt in Washington, D.C.

Nevertheless, some parts of the country are actually relatively peaceful: Somaliland in the north, for example, has functioned more or less independently for several decades.

Pictured: A young fighter from the Al-Shabab militia shows the wound in his hand which he suffered while battling Somali government forces in 2009.

Pictured: A local child stands in a church where a massacre took place in Ntarama, Rwanda. September 16, 1994.

Pictured: Arid North Korean farmland and orchards. 1995.

In the First Congo War, the Rwandan-backed Tutsi militias, led by Laurent Desire Kabila, overthrew the regime of Mobutu Sese Seko.

The Second Congo War began after Kabila (and later his son and successor Joseph) turned his back on his former Rwandan backers; the conflict eventually sucked in countries from across Africa, and although diplomacy ended the war in 2003, fighting continues in the north Kivu region.

Pictured: A Tutsi child soldier at play with an AK-47 during the First Congo War.

With no end is in sight, millions more have fled to neighboring countries and Europe.

Pictured: A Syrian man carries a wounded child following an air strike by government forces in Douma. August 2015.