She was introduced to the occult by the Hermetic Order of the Golden Dawn, and after its break up she launched her own occult society, the Society for the Inner Light. She remained active in the occult for the rest of her life.
She wrote a number of novels and short stories that explored various aspects of magic and mysticism, including The Demon Lover, The Winged Bull, The Goat-Foot God, The Sea Priestess, and The Secrets of Dr. Taverner. This latter is a collection of her short stories, and contains perhaps her most successful efforts at fiction.
Of her non-fictional works on magical subjects, the best remembered of her books are The Cosmic Doctrine, meant as a summation of her basic teachings on mysticism; and The Mystical Qabalah, an introduction to the Kabbalah, at least as practiced by those Western adepts of hermeticism who have borrowed from it. Though some of her writings may seem dated to contemporary readers, they have the virtue of lucidity, and the avoidance of the deliberate obscurity that characterised many of her forerunners.
Dion Fortune allegedly participated in the magical Battle of Britain, which was supposed to have been a gathering of British magicians for the purpose of hexing Adolf Hitler and forestalling a German invasion during the darkest days of World War II. The effort involved in casting these spells is said to have contributed to her death shortly after the war ended. Her Society of the Inner Light continues to function.
"The true nature of the gods is that of magical images shaped out of the astral plane
by mankind's thought, and influenced by the mind."