Does anyone know a good resource for the differences between today's American English and British English of the 1940s? I'm looking for slang terms of the day, different grammar and/or punctuation rules, and words that were common then that aren't really used much today. I've looked around online, but I can't seem to find both in the same article. It's either 1940s American slang or the differences between today's American and British English. :/
Just watch 'Brief Encounter' or look at old popular lyrics. Lots of words like 'queer = strange' and 'gay = happy'. Careful, some old 1940s films like 'Mrs Miniver' have a weird mid-Atlantic quality to the language. I don't think anyone ever spoke like that in real life. It depends a bit on if you mean mainstream southern English (the language of 1940s films and the BBC), less formally-educated speakers of English, or dialect. Dialects have changed quite a lot. But...interesting problem. Your post could lead to a best selling guide. I'm working on it!
If you can receive the channel 'Film 4' then just watch anything before 5pm and chances are it'll be from the 40s.
if relying on films, make sure you only study those that were written and directed by the british, not hollywood takes on our cousins across the pond...
There's a copy of a 1942 film written by Noel Coward you can watch here: http://www.archive.org/details/In_Which_We_Serve It doesn't get much more archetypal than that! Although some of the "Cor blimey, guv'nor!" of the working classes is a bit over the top.
Even a Brit would find it difficult getting 1940s slang accurate, and that's without the UK/US issue. That's good news in a way: you only have to get close, because there are few people alive who could tell whether you had got it spot on. I think you would do better with books than with films (unless you want to know details of pronunciation). I suspect middle and upper class speech is likely to be more accurate than working class speech, because most of the working class speech in fiction of that time seems to have been exaggerated stereotypes. I have a 1940s English dictionary which I picked up at a second-hand book store, which is useful for standard English but dictionaries tended not to include slang in those days.
that's why i included 'screenplays' in the list of what i recommended he study... they can be downloaded at imdb or script-o-rama...
Digitig: I really disagree that few people remember 1940s speech. I have got lots of older relatives who still speak pretty much the same way as they did growing up in the 1930s and 1940s. Think how someone like David Attenborough speaks. As to slang--it's often related to class or region, so the slang they use is only typical of their particular background. My father remembers his public school slang and uses it to annoy us sometimes. It hasn't 'died out' if you happen to be writing about these types of people, especially because they tend to stay within their own peer and class group, and often don't watch TV all that much, so they aren't very affected by trends and buzzwords.
You could try watching old British movies and TV shows set during that time frame such as 'It Ain't Half Hot Mum' and 'Dad's Army'. I'd also point out that the style of speech used by Brit's in the 1940's would vary widely depending on their social and economic circumstances. I'd say that slang back then would be very much a regional thing and possibly not used in polite conversation.
the best way to do it is to research books of that era from both sides of the Atlantic. there is a whole lists of writers and journalists you can look up and read/research the tone of that era.