"The principle based on experience that history is made by the victors in the short run, may be maintained over a middle-range span, but never controlled for a long time, can easily be proven. Our last series of examples involving long-term reinterpretations of the past can testify to this. The structural change of Thucydides' archaeology; divine providence; Machiavellian patterns of behavior; interests, constants, or trends determined by socioeconomic factors - acting human beings can react in some way to all these long-term pregivens, but the pregivens themselves more or less elude their control. It cannot be in the primary interest of the victors to thematize these. Their history has a short-term perspective and is focused on those series of events that, through their own efforts, brought them victory. And when they lay claim to long-term trends, such as divine providence, or a teleological path to the nation-state, real socialism, or liberty, to legitimize their victory historically, this leads very easily to deformations of the view of the past. Think of Guizot's history of civilization, or Droysen's Prussian history, both of which are difficult to sustain even in the face of a textually immanent ideology critique. The historian who is on the side of the victor is prone to interpret short-term successes from the perspective of a continuous, long-term teleology ex post facto.
This does not apply to the vanquished. The first primary experience is that everything happened differently from how it was planned or hoped. If they reflect methodologically at all, they face a greater burden of proof to explain why something happened in this and not the anticipated way. From this, a search for middle- or long-range reasons might be initiated to frame and perhaps explain the chance event of the unique surprise. It is thus an attractive hypothesis that precisely from the unique gains in experience imposed upon them spring insights of lasting duration and, consequently, of greater explanatory power. If history is made in the short run by victors, historical gains in knowledge stem in the long run from the vanquished."

 - Reinhart Koselleck, The Practice of Conceptual History