"form the vast majority"  

The 'majority' consists of the Abrahamic faiths of Christians, Islam and Jews.  The rest are pretty much in single digits worldwide.  

Christianity   2.2 billion 31.50%
Islam  1.6 billion 22.32%
Secular[a]/Nonreligious[b]/Agnostic/Atheist ≤1.1 billion 15.35%
Hinduism 1 billion 13.95%

https://en.wikipedia.org/wiki/List_of_religious_populations

The Christians in the US are the 70% folks.