Leon Trotsky, the exiled Russian revolutionary, was assassinated on this day in 1940. He was sitting at his desk in this studio in Coyoacan, Mexico, when Ramon Mercader – a Spanish-born Soviet agent, posing as Trotsky's friend but really under Stalin's orders – attacked him in the back of the head with a mountaineering ice pick. Trotsky died of his injuries a day later, aged 60. Mercader was found guilty of murder and sentenced to 20 years in prison; he was released in 1960