A brief and very informative history of the clenched fist symbol by Lincoln Cushing can be found at docspopuli.org. Cushing traces back the history of the symbol to 1917 and shows its usage until its gradual decline after the 1970s and today’s only casual appearances. He also highlights a change in the iconographic convention of this symbol during the 1968s. Before it was used in its most simple graphical form at that time, “the fist was always part of something – holding a tool or other symbol, part of an arm or human figure, or shown in action (smashing, etc.)”, he writes.
Phil Patton at AIGA on the other hand discusses what happens when a left wing symbol of resistance and unity becomes commodified in taken up the example of Howard Stern’s radio show on SIRIUS satellite radio.
A relatively recent example of the use of this symbol is the clip by French rapper Medine: