Witness

On the evening of June the 3rd 1989, the Chinese People’s Army opened fire on thousands of students who had been campaigning for democracy in the middle of Beijing.Dan Wang was a 20-year-old student leader from the elite Peking University and was one of the most high profile democracy activists. He says the demonstrators never thought their protests would end in bloodshed. He spoke to Witness History about how the Tiananmen Square crackdown changed his life. (Photo: Dan Wang speaking in Tiananmen Square. Credit: Peter Turnley/Corbis/Getty Images)

Protests about expensive school uniforms in the Central African Republic eventually led to Jean-Bédel Bokassa's fall from power in 1979. The demonstrations started with school children, but soon widened to involve university students. Bokassa ordered brutal reprisals and within months his regime had lost its international support and French troops had invaded. André Nalke Dorogo was a university student at the time and he as been speaking to Ashley Byrne about the events of that year.Image: Jean-Bédel Bokassa on the day he crowned himself Emperor in 1977. Credit:Pierre Guillaud/AFP/Getty Images.

The man who led India to independence and its first Prime Minister, Jawaharlal Nehru, died on May 27th 1964. His niece Nayantara Sahgal spoke to Louise Hidalgo about the great activist and intellectual in 2014.This programme is a rebroadcast.Photo: Jawaharlal Nehru, 1958 (Credit: AFP/Getty Images)

In 1999 a charity was founded in Bangladesh that was dedicated to treating and rehabilitating the survivors of acid violence. The majority of the attacks were against young women, the acid was usually thrown at their faces causing life-altering disfigurement and long-term psychological issues. Farhana Haider has been speaking to Monira Rahman who help set up the charity.Photo: Monira Rahman with survivors of acid attacks 2011 . Credit Monira Rahman)

The environmental campaign group, Greenpeace, was formed in 1971 in western Canada, after a group of activists met in a Vancouver kitchen and decided to sail an old fishing boat to Alaska to stop a US nuclear test. Greenpeace is today one of the biggest environmental organisations in the world, known for its direct action, with offices in over 39 countries. Louise Hidalgo has been talking to one of the founders of Greenpeace, Rex Weyler, about that first campaign.Picture: Members of the original Don't Make a Wave Committee with Greenpeace skipper John McCormack preparing to sail to Amchitka island to try to stop a US nuclear test, 1971 (Credit: Getty Images)

In 2009 Ugandan MPs tried to introduce new laws against homosexuality that would include life imprisonment and even the death penalty. Homophobia was rife in the media with tabloid papers printing the names and addresses of gay men and lesbians. Many activists suffered intimidation and assault. The law was eventually overturned by the Constitutional Court in 2014 but homosexuality is still illegal in Uganda. Victor Mukasa shares his story of fighting for LGBT rights in Uganda, first as a lesbian woman and then as a trans man.(Photo: Ugandan LGBT Activist Victor Mukasa May 2019. BBC)

65 million years ago an asteroid hit the earth, causing the extinction of the dinosaurs along with three quarters of all species on earth at the time. The crater where it hit was discovered on the Yucatan peninsula in 1978 during a geological survey for the Mexican state oil company Pemex. It was named Chicxulub.Lucy Burns speaks to Glen Penfield, who first identified the crater, and Alan Hildebrand, whose research confirmed the discovery.Image: NASA high resolution topographical map of the Yucatan Peninsula created with data collected in the Shuttle Radar Topography Mission and released on March 7, 2003 in Washington, D.C. In the upper left portion of the peninsula, a faint arc of dark green is visible indicating the remnants of the Chicxulub impact crater. (Photo by NASA/Getty Images)

It took 508 days for three friends to complete the first trek along the entire length of the ancient structure, well over 8000 kms. They began in May 1984 and finally reached their destination at the Jiayu Pass on September 24th 1985, having documented the condition of the wall every step of the way. The three men became national heroes as the press followed their progress. Yaohui Dong spoke to Rebecca Kesby in 2017 about what inspired him to make the journey. This programme is a rebroadcast.(PHOTO: Yaohui Dong, Wu Deyu and Zhang Yuanhua. Courtesy of Yaohui Dong)

During the Second World War Nazi officials searched for blonde blue-eyed children in the countries they had occupied. The children were removed from their families as part of a plan to build an Aryan master race. Ingrid Von Oelhafen grew up in Germany and only found out in her 50's that she had been born to Slovenian parents. At nine months old she was taken away and sent to a 'Lebensborn' children's home. She has been speaking to Kate Bissell about what happened during her childhood, and the effect it still has on her life.Photo: Ingrid Von Oelhafen aged about two. Courtesy of Ingrid Von Oelhafen.

The Chinese Communist Party started ruthlessly enforcing birth control in the early 1980s. People with more than one child faced fines, or lost their jobs, or had children forcibly adopted. Yashan Zhao has been speaking to Zhou Guanghong who experienced the policy first-hand, both as a father and as a birth control official.Photo: a propaganda poster extolling the virtues of China's "One Child Family" policy. (Credit:Peter Charlesworth/LightRocket/GettyImages)

In May 2009 the Sri Lankan army finally crushed the Tamil Tiger rebels, ending 25 years of bloody civil war. In the final weeks of the conflict, thousands of civilians were trapped alongside the rebels under heavy shelling as the government forces closed in. Journalists and aid workers were prevented from reaching the war zone. Mike Lanchin has been hearing from one Tamil woman trapped in the siege zone, and from the former UN spokesman in Sri Lanka, Gordon Weiss, who watched on from the capital Colombo as the fighting came to an end.Photo: Tamil civilians standing on the roadside after crossing to a government-controlled area 2kms from the front-line (Getty Images)

In the early 2000s, a handful of experts warned that the world was sleep-walking towards a financial crisis. Among them were South-African born political economist Ann Pettifor and the IMF's chief economist at the time, Raghu Rajan. But their warnings were ignored, and instead in 2008 the world plunged into the worst financial crash since the Great Depression, whose shadow still hangs over our politics. Louise Hidalgo has been talking to the Cassandras of the crash.Picture: Traders at the New York Stock Exchange watch as the Dow Jones share index plunges following the collapse of Lehman Brothers in September 2008 (Credit: Spencer Platt/Getty Images)

In 1979 one of the great engineering feats of the 20th Century was completed and the Karakoram highway between Pakistan and China was finally opened. The highway, known as the Friendship Highway in China, was started in 1959. Due to its high elevation and the difficult conditions under which it was constructed, it is also sometimes referred to as the 'Eighth Wonder of the World'. Farhana Haider has been speaking to Major General Pervez Akmal who worked on the construction and maintenance of the highway.(Photo: The majestic Karakoram mountains on the border of Pakistan and China. Credit: AFP/Getty Images)

One of the most successful TV formats in the world started back in May 2004, bringing ballroom dancing to a new generation. Its format has been sold around the world under the title 'Dancing With The Stars'. Co-creator and executive producer of Strictly, Karen Smith, has been speaking to Ashley Byrne about the show.Photo: Celebrities and professional dancers from Strictly Come Dancing 2018. Credit: BBC.

The first 'war on drugs' was launched by US President Richard Nixon in 1971. He described drug abuse as a 'national emergency' and asked Congress for nearly four hundred million dollars to tackle the problem. Claire Bowes has been speaking to one of Nixon's policy advisors, Jeffrey Donfeld, about an approach to drugs which he describes as more 'find them and help them' than 'find them and lock them up'. And how he convinced the President to roll out a nationwide programme of methadone treatment for heroin addicts. Photo: US President Richard Nixon (BBC)

The groundbreaking Bauhaus school of art and design was founded in Germany in 1919. It would go on to have a huge impact on architecture and design around the world, with the clean lines and minimalist elegance of its distinctive modernist aesthetic influencing everything from skyscrapers to smartphones.In this interview from the BBC archive, Bauhaus founder Walter Gropius explains his goals for the school - and the challenges involved in setting it up.(Photo: View of one of the wings of the Bauhaus building in Dessau, taken on 30 January 2019. Credit: John MacDougall/AFP/Getty Images)

On May 7th 1954, French forces surrendered after a bloody 56-day siege of their base at Dien Bien Phu in the north of Vietnam. Their defeat by the communist independence movement, the Viet Minh, signalled the end of French colonial rule in Indochina. We hear from two veterans who fought on opposing sides in the Battle of Dien Bien Phu. (Photo: A French military Red Cross helicopter preparing to land, while French soldiers try to defend their positions in Dien Bien Phu against the Viet Minh, 1954 Credit: AFP/Getty Images)

The Chinese billionaire set up his online shopping site in 1999. When Alibaba first started, Jack Ma and his team were working out of a small flat in Hangzhou. The BBC's Michael Bristow has been hearing from Duncan Clark, who first worked with the internet entrepreneur in those early days.Photo: Jack Ma attends the World Economic Forum annual meeting in Davos, Switzerland, January 2019. (Credit: REUTERS/Arnd Wiegmann)

In 1948, British colonial authorities declared a State of Emergency in the territory of Malaya, now part of Malaysia. It was in response to the start of a Communist rebellion. From their bases in the jungle, Communist fighters carried out hundreds of guerrilla attacks across the country, targeting Malaya's valuable rubber estates, tin mines, and infrastructure. Alex Last speaks to Gus Fletcher, a decorated former Special Branch officer in Malaya, about his memories of Britain's attempt to combat the communist threat, which became seen by some, as a model for counter-insurgency. Photo: A photograph taken by a British sergeant on patrol in the Malayan jungle.. (Photo by Keystone/Getty Images)

The Argentine ship, General Belgrano, was sunk by a British submarine during the Falklands War on 2nd of May 1982. 323 people died in the attack. Dario Volonte, now an opera singer, was one of the survivors and he spoke to Louise Hidalgo about the attack.Photo: The General Belgrano. Credit: Getty Images