Chuck Klosterman said this quote

Everyone knows history is written by the winners, but that cliche misses a crucial detail: Over time, the winners are always the progressives. Conservatism can only win in the short term, because society cannot stop evolving (and social evolution inevitably dovetails with the agenda of those who see change as an abstract positive). It might take seventy years, but it always happens eventually. Serious historians are, almost without exception, self-styled progressives. Radical views--even the awful ones--improve with age.