Spain and the United States i think
Hinduism grew out of Brahmanism. It became so popular because of its ability to absorb the influence of other religions and because it was generally so tolerable.
The philosophy behind Transcendentalism, to put it plainly, is that humans are pure by nature and that it is society which corrupts them. They also believe that humans are at their very best when they can rely on themselves, whether that be in nature or society.
Hope this helps you!
