Way back in the 1960s the Americans decided they needed a system to provide code numbers for all products so that bar codes could be implemented. Thus the 12-digit UPC was born and duly titled to be universal so as to connote its universality.
Not too long after that, the rest of the world desired a similar system but found that the UPC system lacked sufficient digits for the word (let alone the universe). Thus was born 13-digit WPC.

Sources: http://www.barcodingsolutionsinc.com/bar_code_history.html