"...Caradoc Dearborn, vanished six months after this, we never found his body ..."
-- Mad Eye Moody, showing Harry a picture of the original Order of the Phoenix (OP9)
Caradoc Dearborn was a member of the Order of the Phoenix during the first war against Voldemort. He went missing and was presumed dead (OP9). Harry saw him among the members of the original Order in Mad-Eye Moody’s photograph at Grimmauld Place.
Caradoc was a British Celtic Prince (usually Latinised to to Caractacus) who led a rebellion against Roman rule (Thanks to Ross Gillson).