In 1950, Winnington authored I saw the truth in Korea, an anti-war pamphlet containing photographic evidence of the mass graves of civilians executed by the South Korean police.

The publishing of this leaflet led to the British government debating whether to have Winnington tried for treason, a charge which carried the death penalty, though it was instead decided to make him stateless by refusing to renew his passport.

Now living in China, he grew close to many leading Chinese politicians including Mao Zedong, Zhou Enlai, Liu Shaoqi, and Zhu De.

After becoming disillusioned with Chinese politics and suffering constant harassment, he left China in 1960 with the help of Harry Pollitt and moved to East Germany.

He spent the remainder of his life in East Germany, working as an author of crime-fiction, children's books, and starring as a movie actor in various films.

[9] Within his study of war correspondents, professor of Journalism Phillip Knightley wrote that "Burchett and Winnington were a better source of news than the UN information officers,[10] and if the allied reporters did not see them they risked being beaten on stories".

[13] In August 1950 Winnington published a pamphlet titled I saw the truth in Korea[14] with photographic evidence of mass graveyards containing the corpses 7,000 civilians executed by South Korean police near Taejon.

[15] Embarrassed by Winnington's leaflet, the Cabinet of the British government debated whether they could charge him with "treason",[16] which if found guilty could lead to a death sentence.

[failed verification] An investigation in 1999 leading to declassified US military archives later confirmed Winnington's claims that there was indeed a mass execution of civilians by South Korean forces near Taejon as was documented within I saw the truth in Korea.

After hearing news of slave-owning societies in south China which had been virtually untouched by the Chinese Civil War and Communist Revolution, he set out to investigate.

[citation needed] After months with in Liangshan, Winnington travelled to the border between China and Burma to meet the Wa people, many of whom practiced head-hunting and would keep severed heads in baskets in an attempt to promote crop growth.

[citation needed] After becoming disillusioned with Chinese politics and suffering constant harassment, he left China in 1960 with the help of Harry Pollitt and moved to East Germany.