Theta Kappa Omega (ΘΚΩ), also known by its nicknames TKO or "Teke", was a social Secondary Fraternities for high school–aged men founded in 1872 at California Military Academy in Mayfield, California. The fraternity established local chapters in towns and cities across the United States. The chapters were run by a chapter president, known as the Grand Master, and other elected officers. The national fraternity was governed by an elected body of alumni known as the Grand Council. National conventions were held annually.