Reuben Swinburne Clymer (November 25, 1878 - June 3, 1966) was an American Rosicrucian. He succeeded Edward H. Brown as Supreme Grand Master of Fraternitas Rosae Crucis in 1922, and served until his death, when he was succeeded by his son Emerson Myron Clymer. He had reached the rank of Grand Master in 1905.
The succession from Edward H Brown 'Eulis' to Clymer is questioned by many. Clymer's claim rested instead on having bought Randolph's archive from Randolph's widow, and he created his 'Fraternitas Rosae Crucis' in 1920, two years before Brown died. (Source: Fr Melchior 'Manifestations of the Neo-Rosicrucian Current')
There are claims (unattributed, but possibly by Deveney ? ) that Clymer only attained the second degree in Eulis's Temple of the Rosy Cross, in Boston.
What is not disputed is that Eulis was the holder of Randolph's lineage and that he recognised the Societas Rosicruciana in America. The concordance is on the SRIAmerica website. It is not clear whether the FRC can furnish a similar recognition.
Influenced by the writings of the 19th century occultist and sex magic practitioner, Paschal Beverly Randolph, he kept several of Randolph's books in print (sometimes in heavily edited form) through the middle of the 20th century,
A co-founder of FUDOFSI, which recognized the Fraternitas as the authentic Rosicrucian organization rather than AMORC, he tried to rekindle the organization after the death of leader Constant Chevillon in World War II. After the war he regarded the FRC as the world, rather than American, headquarters of Rosicrucianism.
In Brazil and in some other South American countries, the FRC merged with branches of Arnoldo Krumm-Heller's Fraternitas Rosicruciana Antiqua (FRA) to the extent that the two became indistinguishable.
Many FRA groups became disenchanted with Krumm-Heller's teachings, and the branches merged with the FRC no longer accepted the Law of Thelema.
Clymer was a prolific writer. His titles include: Alchemy and Alchemists, Vol.s 1 and 2 (1907) All-Seeing Eye: Teachings of the Rose Cross College Ancient Mysteries Ancient Mystic Oriental Masonry (1907) Book of the Rosicruciae, Vol.s 1, 2, and 3 Brotherhood of the Rosy Cross Christ Birth: Teachings of the Rose Christisis or Higher Soul Culture Compendium of Occult Law The Confederation or Fraternity of Initiates (1930) Constitution of the Knights of Chivalry Destructive Negative Yogaism Divine Law of Mastership (1922) Failures Fire Philosophy: The Foundation of All True Initiation Freemasonry and Its Occult Inner Secrets Gods (1910) Heaven: The State of Happiness Must Be Found on Earth The Hermetic Concept of Success Higher Race Development: A Course of Instructions on the Right Use of Sex (1919) How to Have Your Own Will Come True The Initiates and the People, Vol.s 1 - 5 (1928-1934) The Interpretation of St. John (1913) Law of Freedom Leaders The Magnetic Power of the Mind Making Health Certain (1921) Man and the Great Beyond Medicines of Nature: The Thomsonian System (1905) Militia Crucifera Mystic Masonry Natural Hypnotism and Suggestive Therapeutics in the Natural Sleep (1902) Occult Initiation The Power of Thought Protection Through Divine Law Rosicrucian Interpretation of Merlin Rosicrucian Interpretation of Sir Percival The Science of the Soul Secret Schools Sex Teaching in Public Places Soul Consciousness is the Way to Christhood (1925) Soul's Descent Suffer Not Injustice to be Done Temple Dedication Service of the Church of Illumination and many more.