Theosophy
Helena Blavatsky's, theosophy, a blend of Western Occultism and Asian religious philosophy, proposed the existence of a society of Secret Chiefs called the Great White Brotherhood. Later offshoots of the Theosophical Society used the term Ascended master or Mahatma.
In the Ascended Master Teachings, Ascended Master are believed to be spiritually enlightened beings who in past incarnations were ordinary humans, but who have undergone a series of spiritual transformations originally called initiations.
Both "Mahatmas" and "Ascended Master" are terms used in the Ascended Master Teachings. Ascended Master is based on the Theosophical concept of the Mahatma or Master of the Ancient Wisdom. However, "Mahatmas" and "Ascended Masters" are believed by some to differ in certain respects.
Read more about this topic: Secret Chiefs