Wow, I should have known you guys would be good at this sort of thing. I should have asked for the exact year, just to make it a bit of a sport.
Marie-Noelle, Jenny Wren, redsilvia, Tanit-Isis, Readythreadsew and AlisonMM, you are all absolutely right: this picture is from the 1930's. From 1935, to be precise.
And indeed, I put it on the blog as a guess-the-decade topic because the outfits on their own could easily be mistaken for 1970's styles. You know: flares, funky decoration, bare skin and no bras...
But all of you were too smart to fall for that.
P.S. Thank you all for your kind comments to yesterday's post.