Just over a hundred years ago London hosted its first Olympic Games by chance when  Rome, the chosen host city, pulled out after the eruption of Mount Vesuvius in spring 1906.   The crisis threatened to halt Baron de Coubertin’s cherished revival of the Olympic Games.   A group of gentlemanly English sporting enthusiasts offered to mount the Fourth Olympiad in London.  They had two years, no budget and no suitable venue.  If they failed there was a chance that Baron de Coubertin’s Olympic movement would end in 1908.  Illustrated with over 70 contemporary images, this social and sporting history provides a thought-provoking contrast to the forthcoming 2012 London Olympic Games.