The 60s brought some of the best R'n'B records ever made imo. Listen to this for example (produced by Leiber&Stoller btw):
https://www.youtube.com/watch?v=prlWGe2EHro
https://www.youtube.com/watch?v=prlWGe2EHro
I'd never given a thought to where that song came from, but this is stunning. So is gf's Barbara Lewis song (which I heard at the time it was released). Those backing vocals!
The US charts in the early '60s were certainly full of surprises. Dick and Dee Dee's "The Mountain's High", a huge favourite of mine, was utterly out of left field (and a B-side to boot) but reached #2 in 1961. That vocal stack is really weird but it works!
https://www.youtube.com/watch?v=LU2rjoSXI34