Indigenous peoples in Mexico and the United States have consumed peyote for millennia. It has also been the subject of interest and concern among Euro-Americans since the Spanish Conquest of Mexico. . Amid growing use by non-Native people, peyote was first banned by the Spanish Inquisition in 1620. While the historical record in the immediate period after the Inquisition left Mexico in 1824 is sparse, extant evidence suggests that peyote continued to circulate in herbal markets as a treatment for any number of maladies. Beginning in the late 19th century, peyote was the subject of significant scientific interest (mainly around the treatment of mental disorders), along with a growing fascination with and concern over its use in Indigenous communities in Mexico and the United States. Peyotism in Mexico at this point was a long-standing tradition among a limited number of communities, and it was linked to the evangelical cultural revivalist Native American Church in the United States. Use by non-Native persons (in both formally therapeutic settings and more informal settings) expanded considerably during the 1950s and 1960s. Peyote would ultimately be banned in the United States in 1965 and Mexico in 1971, although in both cases exceptions were made for Indigenous peyotists. Currently, peyote is the subject of a series of ecological concerns, as peyote habitats on both sides of the border have been threatened by climate change, economic development, and overharvesting.