Answer
Lack of Buddhist rights was a primary factor in Diệm's unpopularity. Despite Buddhists comprising 70-80% of the population, the government was dominated by Catholics, including Diệm himself. This favoritism led to discrimination, political oppression, and even military violence against Buddhists. The most notable incident was the 1963 Huế Phật Đản shootings, where government forces fired upon unarmed Buddhist protesters, further inflaming tensions and solidifying Diệm's downfall.