Charles Mason Remey (May 15, 1874 – February 4, 1974) was a prominent and controversial American Bahá'í who was appointed in 1951 a Hand of the Cause, and president of the International Bahá'í Council. He was the architect for the Bahá'í Houses of Worship in Uganda and Australia, and Shoghi Effendi approved his design of the unbuilt House of Worship in Haifa, Israel.
When Shoghi Effendi died in 1957, he died without explicitly appointing a successor Guardian, and Remey was among the nine Hands of the Cause elected as an interim authority until the election of the first Universal House of Justice in 1963. However, in 1960 Remey declared himself to be the successor of Shoghi Effendi, and expected the allegiance of the world's Bahá'ís. Subsequently, he and his followers were declared Covenant breakers by the Hands. They reasoned that he did not fulfill the qualifications set forth by Abdu'l-Bahá in His Will and Testament. Remey lacked a formal appointment from Shoghi Effendi, an appointment which needed to be confirmed by the rest of the Hands, and that the office was confined to male descendants of Bahá'u'lláh, the Aghsan, which Remey was not. Almost the whole Bahá'í world rejected his claim, but he gained the support of a small but widespread group of Bahá'ís. His claim resulted in the largest schism in the history of the Bahá'í Faith, with a few groups still holding the belief that Remey was the successor of Shoghi Effendi. Various dated references show membership at less than a hundred each in two of the surviving groups.
Born in Burlington, Iowa, on May 15, 1874, Mason was the eldest son of Rear Admiral George Collier Remey and Mary Josephine Mason Remey, the daughter of Charles Mason, the first Chief Justice of Iowa. Remey’s parents raised him in the Episcopal Church. Remey trained as an architect at Cornell University (1893–1896), and the École des Beaux-Arts in Paris, France (1896–1903) where he first learned of the Bahá'í Faith.