William Walker Atkinson was a prolific author and a publisher (among other things, including a lawyer and a merchant).
He was an early pioneer of the "New Thought" movement. He also wrote under the pseudonyms "Yogi Ramacharaka" and "Theron Q. Dumont". He was born
December 5, 1862 and died November 22, 1932.

Here is one the best sources of information about him:

William Walker Atkinson Home Page (wwwhubs.com)