The History Hour

Twelve tonnes of ivory was set alight by President Daniel Arap Moi in Nairobi National Park in July 1989, to highlight the threat from poaching. The ivory burn was organised by conservationists who wanted to save the world's elephants. Plus, the closure of Britain's ground-breaking Common Cold Unit; Cuba executes top military officers, the Chinese allow sales of tampons and the first modern lesbian. (Photo: Ivory tusks arranged in a pile and set alight. Credit: Andrew Holbrooke/Corbis/Getty Images)

Life under the Khmer Rouge in the 1970s, the Germans kidnapped by the Contras in Nicaragua in the 80s, plus how Aboriginal women took on the Australian government against nuclear waste, Anita Hill's stand against the promotion of Judge Clarence Thomas to the US Supreme Court and the birth of the Sony Walkman. (PHOTO: CHOEUNG EK, CAMBODIA - 1993/02/01: Skulls are piled up at a monument situated outside Phnom Penh to serve as a constant reminder of the genocide under the Khmer Rouge during the Pol Pot years.. (Photo by Peter Charlesworth/LightRocket via Getty Images)

The riot that inspired the modern gay rights movement; Saddam Hussein's 1980s genocidal campaign against Iraq's Kurds; notorious British serial killers, Fred and Rose West; 50 years of fighting for fat people in America; and Joseph Heller on his seminal work, Catch-22. Picture: the Stonewall Inn today (Getty Images)

An African-American civil rights hero, a Chinese online star, the tragic icon of Iran's reform movement and archive recordings of the psychoanalyst CG Jung. Plus the great violinist Yehudi Menuhin's love of yoga. Photo:Roy Wilkins and Medgar Evers Being Arrested on 1st June 1963 in Jackson, Mississippi. Credit: Getty Images

How a 1950s drug helped revolutionise the treatment of mental illness. Also, how hundreds of thousands of Kosovans fled when NATO bombed former Yugoslavia. Plus, a monumental public artwork in post-Cold War Berlin, Chinese-American relations after WW2, and a trailblazing same sex wedding in the 1970s. Photo: Nurses prepare a patient for electric shock treatment in a psychiatric hospital. (Hulton-Deutsch Collection/CORBIS/Getty Images)