I too am a history major. Secondary subjects were Latin and History of Religion. Anyone who thinks explicit language is a 20th century invention is needs to read up. Catullus is a good starting point, and please, do not miss out on Rochester's works from the late 17th century or Wilkes' Essay on Woman from the 1760s. Also, some Victorian erotica, perhaps?
As for the existence of crossdressing, homosexuality and drugs in the 20s, any biography on a member of the 'Bright Young People' will tell you abou thar, but then you can also simply read something by Evelyn Waugh...
As for the existence of crossdressing, homosexuality and drugs in the 20s, any biography on a member of the 'Bright Young People' will tell you abou thar, but then you can also simply read something by Evelyn Waugh...