[1] Shortly after the Khmer Rouge captured Phnom Penh at the end of the Cambodian Civil War, the cathedral was destroyed.

A Bishop's Palace[6] and a church library[7] were built adjacent to the cathedral, which was hailed as an "architectural legacy of the French" by The New York Times.

The new atheistic[8] regime declared the country would go back to "Year Zero"[2] and destroyed anything capitalistic,[8] religious[11] or evoking the colonial past.

[12] To the Khmer Rouge, the cathedral epitomized all three characteristics and, as a result, it was the first building in the capital city to be destroyed under their new government.

[15] The cathedral was one of all the seventy-three Catholic churches around the country to be obliterated in 1975, the first year of Khmer Rouge rule of Cambodia.

[11] Despite its complete destruction, the empty land where the cathedral once stood became the location of a multi-faith Christmas celebration in 1979, the year the Khmer Rouge's regime was overthrown.