Do any religions that originated in North or South America before 1492 still have large numbers of believers? More than, say, “classic” but relatively rare faiths like Zoroastrianism or Shinto (a few million believers worldwide)?
If not, were they effectively killed off by European conquest, or did individual religions that evolved in the Americas ever have the kind of mass numbers that Christianity, Islam, or Hinduism achieved?
Many aboriginal people in Canada practise pre-Christian religious traditions, or reconstructions thereof.
The 2001 census says that 29,820 people listed their religion as aboriginal spirituality, a 175% increase over the previous census. The same census counted 976,305 people as aboriginal (First Nations, Métis, and Inuit).
So at that time there wasn’t a large community of people identifying their religion as aboriginal spirituality, but it was growing. Also, I imagine others practise aboriginal spiritual traditions in various ways without identifying it as their religion.
In much of Latin America, in areas with a large indigenous population the people practice a religion that is really a synthesis of Christianity and traditional beliefs. Although nominally they are Roman Catholics, in reality the practice owes a great deal to pre-Columbian religions.
A good example is the religion practiced in Mayan areas of southern Mexico and Guatemala.
The present Mayan population is estimated at 6 million or more. If we assume that half of them practice this hybrid religion, that’s a sizeable number of people still practicing traditional beliefs at some level.
We Native Americans sometimes practice indigenous religions or a syncretism of indigenous and Christianity.
My tour guide in Tulum, Mexico told the group that many (most?) of the native Mayans in the area “do not worship Jesus Christ [sic]” and instead worship the Mayan gods. Not sure how true this is.