blue murder

Have you cried blue murder lately?  If so you have produced a faint echo of what was an extremely forceful exclamation in the 1660s in both England and France.  Mort Dieu! they would shout.  God’s death!  Taking the name of the Lord in vain at that time in history caused serious conniptions.  And so, along with the fierce exclamation came the euphemistic sidestepping variant for those fainthearted souls who couldn’t bring themselves to mention God.  They would say Mor bleu. This was spelled variously, sometimes as Mort bleu.  By the early 1800s it had been translated into English as blue murder.  It was always in a phrase that had yell or cry in it where blue murder is taking the place of the exclamation.  The first citation in the OED is dated 1828 and reads:  I gives Jenny a grip … as makes her squall blue murder. And Blue-murder is listed in a dictionary of slang of the period defined as ‘a desperate or alarming cry’.

Of course crying blue murder today breaks no taboos.  That said, a rock band did regard it as an appropriate name for the band so it must have still had some edge.