Seeing Linda write "That'll be the day!" in another topic recently reminded me of a question about the origin of this expression.
A book about New Zealand English claimed the phrase originated there. The book even had an anecdote about a US serviceman in NZ during the 2nd World War, who heard the expression but didn't grasp its usage. When some locals kindly said they would invite him to their home, he said, "That'll be the day!", thinking he was expressing enthusiasm at the prospect.
But I couldn't help wondering about this. The expression is now well-known around the world, and presumably it was well-known as far back as the 50s when Buddy Holly used it as the title of a song. And it seems the song was inspired by a John Wayne movie in which the expression was used as a catch-phrase by the John Wayne character.
Did the phrase make its way from NZ to the US some time between the War and the making of the film? Did the serviceman who got it wrong subsequently become a screenwriter and try to expunge the memory of his faux pas by using the phrase properly in a script?
I wonder if anyone in the forum can shed any light on this?
