The first recorded nicknames in the school newspapers ('Iolani Newsette, The Inlook and Imua 'Iolani) were the Nuuanuans, Iolanians and Blue and Whites. Those nicknames were used prior to 1936, when 'Iolani entered the Interscholastic League and switched its school colors to red, black and white. Legendary football head coach Fr. Kenneth A. Bray decided upon the change because too many other teams in the league wore blue uniforms.
According to "The Ol' Man" (by Ronald Oba '42 and Don Johnson), when that switch took place, the 'Iolani football team became known as the Crimson Tide. That nickname stuck around until the early 1950s.
During those years, 'Iolani teams also were still referenced as the Nuuanuans, in addition to a few new nicknames, including Missionaries (mentioned in "The Ol' Man") and Braymen (mentioned in school publications).
In 1938, the first known reference to Raiders and Red Raiders was made in the Honolulu Advertiser and Ka Mo'olelo O 'Iolani. However, Crimson Tide was still in play and the football team was referred to as the Crimson Tide Red Raiders in 1953. Junior varsity squads were called the Iolani Babes and Raider Babes by Imua 'Iolani sportswriters.
For most of the last half century, 'Iolani teams have been known as the Red Raiders.
A few years after the school went co-ed in 1983, girls teams were referred to as the Lady Raiders for a brief time in Imua 'Iolani.
In the early 1990s, the school officially dropped the "Red" and has since used the nickname Raiders.
-- John Tamanaha '87
(Source: 'Iolani School Archives)