Re the thread title -- it should surely read 50s, 60s, 70s. The OP mentions skiffle as his first point. Skiffle groups -- Vipers, Russ Cray & Hylda Syms, Henry Morris Group, Chas McDevitt, Easy Riders, Donegan &c — all originated and flourished from the mid-1950s; I have confirmed this on Wikipedia. And it was from these that the folk club scene emerged. I regularly attended the succession of clubs that operated at the Princess Louise, the Cranbourn, the Bread Basket &c, from 1955 onwards.

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