The Hoa Hao movement was found by a man called Huynh Phu So in1939. It gained great popularity in the fertile Mekong Delta area. It drew. on religious ideas popular in anti - French uprisings of the nineteenth century. Huynh Phu So's criticism against useless expenditure has a wide appeal. He also opposed the sale of child brides, gambling and the use of alcohol. French put him in mental asylum. Interestingly, the doctor who had to prove him insane became his follower in 1941. Even the French doctors declared that he was insane. The French authorities exiled him to Laos and sent many of his followers to concentration camps.