Songfacts®:

• Any uniformed person hearing this song might think it was about a groupie, a petty sadist, some sort of pervert, or just a plain old hypocrite, but Mary Long is actually a composite character.
  
  Mary Whitehouse (1910-2001) was the founder of the National Viewers' and Listeners' Association, whose remit was to clean up television which she perceived as corrupting the nation's morals.
  
  Lord Longford (1905-2001) was an eccentric aristocrat who was Christened Lord Porn after he visited a number of strip clubs as part of his research and walked out indignant at their displays of indecency.
  
  Mrs. Whitehouse began her campaigning in 1963 and founded her organization in November 1965, which by pure coincidence or no coincidence at all, was when the dreaded F word was first used on British TV, by Kenneth Tynan. In view of the deluge of filth that has emanated from the boob tube since, an objective critic might rightly claim she was unsuccessful. Her one resounding success came in 1977, four years after "Mary Long", when she initiated an action for blasphemous libel against the homosexual publication Gay News which had published a grossly blasphemous (and depraved) poem written by an academic which portrayed the violation of the body of Jesus Christ by a homosexual necrophiliac Centurion.
  
  If Lord Longford sparked ridicule for his campaigning against pornography, he inspired contempt by his campaigning for the Moors Murderess Myra Hindley. On the plus side, he worked for the rehabilitation of many other prisoners who unlike Hindley were not beyond redemption.
• "Mary Long" is a group composition, but vocalist Ian Gillan, who wrote the lyrics with help from bass player Roger Glover, explained the reason for their attack on "the self-appointed guardians of public morals in England's early seventies" pointing out that "Roger and I clearly were not suggesting that either Whitehouse or Longford would stoop to drowning kittens or drawing a piece of graffito on a toilet wall [as in the song] but there is and always has been a sinister whiff of hypocrisy emanating from the pulpit of the pious."
• The line "Mary told Johnny not to write such trash" is a parochial reference that needs some explaining. The scriptwriter Johnny Speight (1920-98) was the creator of Alf Garnett, a bigotted working class moron who was portrayed by Warren Mitchell in the BBC TV situation comedy Till Death Us Do Part. The series ran from 1965-75, and Alf Garnett would swear freely throughout, peppering his dialogue with the word bloody (and the occasional racial epithet). Although bloody was not a particularly strong word even then, and in the next millennium doesn't even raise an eyebrow, its constant use irked Mrs. Whitehouse, who complained on one occasion that she doubted if many people would use 121 bloodies in half an hour. >>

  Suggestion credit:
  Alexander Baron - London, England, for all above