Ankle chains have been claimed to be a sign of ************, although no authoritative source exists for this. I did once have a girlfriend who told a story of how she wore one once and a member of her church complained to her father on those grounds. His very sensible and fatherly response was 'if you think my 13 year old daughter is a **********, the problem is in your filthy addled mind, not in her choice of jewellery.' Or something along those lines. In Arabic countries, it is thought that some women use them to attract men, jingling them to make notice but then, here in the UK Morris Dancers go round festooned with bells and no one accuses them of loose morals. I've seen women wearing them, both white and Asian women - no BBC or spade ornaments attached and they certainly do look attractive... along with the rest of the woman, in my experience. It's just another adornment they use, to great effect, often.
Ankles being down at the bottom of the leg, I suspect it all has something to do with hemlines, footsie, how much you could get away with showing when mores were awfully restrictive about that sort of thing along with the fact that in some Victorian households, piano legs (yes, you read that right) had linen covers made for them, in order not to over excite the menfolk.