Theos Casimir Bernard was the third American to enter Lhasa in Tibet in 1936. There he was initiated into the practice and philosophy of Tibetan Buddhism, apparently being accepted there as the reincarnation of Padma Sambhava. While there, he studied Tantric yoga in order to understand the principles behind it. He then wrote about his experiences in books, newspaper articles and a personal memoir.
Back in the United States in 1939, he opened the American Institute of Yoga and Pierre Health Studios. Bernard returned to India and Pakistan in 1947 and, while on expedition in the Himalayas, he disappeared. Later he would be declared dead, though his body was never found.