In April of 1975 the communist Cambodian army (known as the Khmer Rouge) finally overwhelmed and conquered the pro-Western Cambodian army (ostensibly backed by the United States). The communists entered the capital city and immediately began implementing their concept of “Year Zero”.
The communists believed that everything associated with the former government or even the entire culture of Cambodia was corrupt and needed to be erased. Not just books or artwork or businesses or schools needed to be destroyed…but people themselves needed to be liquidated. Believing themselves to be morally superior to all others, they were going to re-start “civilization”, and the beginning would be called “Year Zero.”
The communists (Marxist socialists) targeted anyone with a link to the former regime, anyone who count possibly tell the history of Cambodia to future generations. The communists targeted schoolteachers, Buddhists, Catholics, businessmen, former government workers, ethnic minorities (Chinese, Vietnamese, Cham people), and slaughtered them. Even people who wore glasses, even people who spoke multiple languages, were murdered. (“Intellectuals” had a memory of what happened before “utopia” began with the Marxist socialists, so of course they were a threat that had to go.)
The Marxist socialists sent them to labor camps, starved them to death or worked them to death, or simply murdered them with pickaxes (to save a bullet).
Almost 2 million innocent people were murdered by the Marxist socialists, who believed it was their calling to erase an entire culture and bring in a perfect society.