According to an analysis by the Pew Research Center, in 2010 about 45.3% of the Vietnamese adhere to indigenous religions, 16.4% to Buddhism, 8.2% to Christianity, 0.4% to other faiths, and 29.6% of the population isn't religious.[140]
According to the General Statistics Office of Vietnam's report for 1 April 2009, 6.8 million (or 7.9% of the total population) are practicing Buddhists, 5.7 million (6.6%) are Catholics, 1.4 million (1.7%) are adherents of Hòa Hảo, 0.8 million (0.9%) practise Caodaism, and 0.7 million (0.9%) are Protestants. In total, 15,651,467 Vietnamese (18.2%) are formally registered in a religion.[141] According to the 2009 census, while over 10 million people have taken refuge in the Three Jewels of Buddhism,[142][143] the vast majority of Vietnamese people practice ancestor worship in some form. According to a 2007 report, 81% of the Vietnamese people do not believe in God.[144]
About 8% of the population are Christians, totalling around six million Roman Catholics and fewer than one million Protestants. Christianity was first introduced to Vietnam by Portuguese and Dutch traders in the 16th and 17th centuries, and was further propagated by French missionaries in the 19th and 20th centuries, and to a lesser extent, by American Protestant missionaries during the Vietnam War, largely among the Montagnards of South Vietnam.