Origins & history

The order was established around the turn of the twentieth century by Carl Kellner and Theodor Reuss in Germany, drawing on a mix of Masonic high-degree systems, Rosicrucian currents, and material claimed to derive from contact with esoteric teachers in the East. Aleister Crowley was admitted to the order by Reuss in 1910 and within a few years had been authorised to head its English-speaking work.

Crowley substantially rewrote the order’s rituals to align with Thelema, and after a period of organisational fracture in the mid-twentieth century the present-day O.T.O., with its headquarters in the United States, emerged as the largest of several bodies claiming the lineage.