[4] In 1942, Khieu Chom joined the Umbrella Revolution along with other nationalist monks such as Hiem Chieu in Phnom Penh who were opposed to the French protectorate.

All these political prisoners were released at the end of the Second World War and Khieu Chom returned to his studies as a monk in Wat Langka.

"[6] Some even presume that he was "a member of a small group of people responsible for planning the Cambodian coup of 1970 which overthrew the monarchy.

"[citation needed] While he was supportive of the Republic and helped drafting the republican constitution, his conservative views were at odds with many policies imposed by Lon Nol.

[6] Cronyism and association with the Republican government was severely judged by the Khmers Rouges once they entered Phnom Penh in April 1975, leading to his execution with other monks for alleged “CIA” sympathies and “enemy” activities.”[3] Chum was a student of Hem Chieu, a leading figure in the early period of modern Khmer nationalism.