In 2014 episode of BrainStuff – HowStuffWorks, host Jonathan Strickland explains the origins of the very deliberate pattern of speech known as the Transatlantic (Mid-Atlantic) Accent, some of the theories as to why it was so ubiquitous in early Hollywood and why it isn’t employed that much anymore.
So what happened to this accent? Linguist William Labov notes that Mid-Atlantic speech fell out of favor after World War II, as fewer teachers continued teaching the pronunciation to their students. That’s one of the reasons this speech sounds so ‘old-timey’ to us today: when people learn it, they’re usually learning it for acting purposes, rather than for everyday use. However, we can still hear the effects of Mid-Atlantic speech in recordings of everyone from Katherine Hepburn to Franklin D. Roosevelt and, of course, countless films, newsreels and radio shows from the 30s and 40s.