@DJDarren @labr #ThePlaylistSuggestion
First thought was to skip this. I have no idea who became big and who didn't. Many times I've started listening to what I thought was a new and unknown artist, only to find they've been huge for a decade.
But what I do know is Northern Soul. And though some stars on the scene were big names (like Eddie Floyd or Edwin Starr), much of the scene was obscure acts, some of whom later had a career rebirth in the north of England. That obscurity after all is where the Northern Soul tag came from - Northern Soul, as opposed to the regular soul that everyone else listens to.
So I hope you don't mind me spamming some otherwise overlooked Northern Soul legends:
Dolores Johnson - What Kind of Man Are You?
(sometimes listed as Delores or Doleres or variations on that theme, or sometimes Dee Dee - as far as I know, and the name changes make it difficult to be sure, she released three singles and none of them were successful)
Sandi Sheldon - You're Gonna Make Me Love You
(aka Kendra Spotswood, a respected backing singer in the 60s, but had no success as a lead artist before being rediscovered on the Northern Soul scene in the 70s)
The Carstairs - It Really Hurts Me Girl
(ultimately quite an influential live band, but commercially had zero success and only released a couple of singles)
Charles Thomas - Man with the Golden Touch
(not to be confused with Charlie Thomas, founder of one incarnation of The Drifters, nor indeed any of the many other musicians with the same name - this one seems to have only released one single)
Roy Redmond - Ain't That Terrible
(sometimes listed as Roy Redman, released two unsuccessful singles in 1967)
Mamie Galore - It Ain't Necessary
(aka Mamie Davis, another backing singer who tried and failed to become a commercially successful solo artist. Later became a respected blues musician in Mississippi.)
(that's probably enough for now but I really could go on all day)